Compacted Fibrous Structure Articles and Methods for Making Same

ABSTRACT

Compacted fibrous structure articles and methods for making the same are provided.

FIELD OF THE INVENTION

The present invention relates to compacted fibrous structure articles and more particularly to compacted fibrous structure articles that exhibit differential density and/or differential thickness, for example that exhibit one or more regions that are compressed and one or more regions that are uncompressed and/or substantially uncompressed, and even more particularly to compacted fibrous structure articles comprising a fibrous structure comprising a plurality of pulp fibers, for example paper, such as a wet-laid fibrous structure, and/or other nonwoven fibrous structure and methods for making the same.

BACKGROUND OF THE INVENTION

Known compacted fibrous structure articles comprise non-textured, non-patterned, non-embossed woven, for example cotton, and/or nonwoven fibrous structures that have been compressed into uniform or substantially uniform density and/or uniform or substantially uniform thickness. A few of the known compacted fibrous structure articles comprise a non-textured, non-patterned, non-embossed fibrous structure that is compressed into a compacted fibrous structure article such that during compression a “stamp”, such as a logo is imparted to the compacted fibrous structure article. This “stamp” on the compacted fibrous structure article is not the same as the fibrous structure making the compacted fibrous structure article being textured, patterned and/or embossed, for example where a random pattern and/or non-random repeating pattern covers substantially the entirety of a surface of the fibrous structure.

Further, most of the known compacted fibrous structure articles 10 are compressed, for example in a random manner, into cylindrical forms, like discs and/or pucks, for example as shown in Prior Art FIG. 1A. However, some of the known compacted fibrous structure articles, for example known compacted fibrous structure articles 10 comprising a woven fibrous structure, for example a fabric, such as bath towels and/or wash cloths, are compressed into rectangular forms for example as shown in Prior Art FIG. 1B. In addition, Prior Art FIG. 1C is an example of a known compacted fibrous structure article 10 exhibiting uniform or substantially uniform density and/or uniform or substantially uniform thickness that includes a “stamp”, for example a “T” on a surface of the compacted fibrous structure article. As can be seen in Prior Art FIG. 1C no other part of the compacted fibrous structure article 10 includes texture, pattern, or emboss besides the lone “T” stamp.

Further, such known compacted fibrous structure articles exhibit significant consumer negatives, for example their stiffness is extremely high, they exhibit less than desirable absorbency, they exhibit less than desirable softness, and they don't open to their uncompacted form very easily, for example at least partially due to the process for making the known compacted fibrous structure article that includes rolling and compressing a fibrous structure into a high uniform density and/or high substantially uniform density (average densities of greater than 0.75 g/cm³ and/or greater than 0.70 g/cm³, which negatively impacts the (re)openability) compacted fibrous structure article and/or into a low uniform thickness and/or low substantially uniform thickness, similar to a puck, and/or no tab for grasping the known compacted fibrous structure article during the opening process, resulting in a user requiring two hands to open the known compacted fibrous structure article. Therefore, the only way to open these known compacted fibrous structure articles is to contact and/or saturate the known compacted fibrous structure articles with water and let them expand uncontrollably like a sponge after which a user of the article has to try to open the expanded fibrous structure article from its uncompressed form/state to its uncompacted form/state, which is challenging due to the lack of a clearly visible opening mechanism, such as a tab within the article for grasping to help facilitate opening of the known compacted fibrous structure article.

To illustrate the challenges with opening a known compacted fibrous structure article during use, Prior Art FIG. 1D illustrates the opening process for a known compacted fibrous structure article 10. The known compacted fibrous structure article 10 is opened by contacting the known compacted fibrous structure article 10 with water 12, for example from a faucet 14, such that the known compacted fibrous structure article 10 swells and expands, for example as represented by the arrow A, from its compressed form to a less compressed form 16. Continued contact of the less compressed form 16 with water 12, for example from a faucet 14, continues the swelling and expansion, for example as represented by arrow B, from its less compressed form 16 to a less than less compressed form 18. Once the less than less compressed form 18 has reached its uncompressed form 20, for example a fully uncompressed form, a user will require two hands 22 to fumble around the surface 24 of the uncompressed form 20 to try to locate an edge of the fibrous structure 26 that forms the uncompressed form 20. Once a user locates an edge of the fibrous structure 26 the user can unroll and optionally unfold, if necessary, the uncompressed form 20 into the uncompacted fibrous structure article 28, such as a wipe and/or paper towel.

There is a need for a compacted fibrous structure article, for example a compacted fibrous structure article that exhibits a differential density, for example that exhibits one or more regions that are compressed and one or more regions that are uncompressed and/or substantially uncompressed, and/or a compacted fibrous structure article comprising a fibrous structure comprising a plurality of pulp fibers, for example wood pulp fibers, such as paper, for example a wet-laid fibrous structure, and/or other nonwoven fibrous structure, for example another nonwoven fibrous structure, such as a co-formed fibrous structure, comprising a plurality of pulp fibers, for example wood pulp fibers, that overcomes the negatives associated with the known compacted fibrous structure articles and methods for making the same.

SUMMARY OF THE INVENTION

The present invention fulfills the needs set forth above by providing a compacted fibrous structure article, for example a compacted fibrous structure article that exhibits a differential density, for example that exhibits one or more regions that are compressed and one or more regions that are uncompressed and/or substantially uncompressed, and/or a compacted fibrous structure article comprising a fibrous structure comprising a plurality of pulp fibers, for example wood pulp fibers, such as paper, for example a wet-laid fibrous structure, and/or other nonwoven fibrous structure, for example another nonwoven fibrous structure, such as a co-formed fibrous structure, comprising a plurality of pulp fibers, for example wood pulp fibers, that overcomes the negatives associated with the known compacted fibrous structure articles and methods for making the same. comprising a fibrous structure that exhibits a lower stiffness and/or higher absorbency and/or higher softness and/or more effective opening, for example utilizing a tab on the compacted fibrous structure.

In one example of the present invention, a compacted fibrous structure article as set forth herein and in the claims is provided.

In another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article such that the compacted fibrous structure article exhibits differential density, for example the center of the compacted fibrous structure article is less dense than one or more of the edges of the compacted fibrous structure article, is provided.

In another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article such that the compacted fibrous structure article exhibits differential density, for example the center of the compacted fibrous structure article is more dense than one or more of the edges of the compacted fibrous structure article, is provided.

In another example of the present invention, a compacted fibrous structure article comprising a border, for example a border that is visually discernible from at least one other portion of the compacted fibrous structure article, for example exhibits a different texture and/or comprises a print or a different print than the other portion, is provided.

In another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article such that the compacted fibrous structure article exhibits an Average Overall Density of less than 0.70 g/cm³ and/or less than 0.65 g/cm³ and/or less than 0.60 g/cm³ and/or less than 0.55 g/cm³ and/or less than 0.50 g/cm³ to greater than 0 g/cm³ and/or greater than 0.05 g/cm³ and/or greater than 0.10 g/cm³ as measured according to the Micro-CT (μCT) Compacted/Compressed Fibrous Structure Article Test Method, is provided.

In another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article such that a center region of the compacted fibrous structure article exhibits a μCT Density of less than 0.70 g/cm³ and/or less than 0.65 g/cm³ and/or less than 0.60 g/cm³ and/or less than 0.55 g/cm³ and/or less than 0.50 g/cm³ and/or less than 0.45 g/cm³ and/or less than 0.40 g/cm³ and/or less than 0.35 g/cm³ and/or less than 0.30 g/cm³ to greater than 0 g/cm³ and/or greater than 0.05 g/cm³ and/or greater than 0.10 g/cm³ as measured according to the Micro-CT (μCT) Compacted/Compressed Fibrous Structure Article Test Method, is provided.

In another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article such that an edge region of the compacted fibrous structure article exhibits a μCT Density of less than 0.70 g/cm³ and/or less than 0.65 g/cm³ and/or less than 0.60 g/cm³ and/or less than 0.55 g/cm³ and/or less than 0.50 g/cm³ and/or less than 0.45 g/cm³ and/or less than 0.40 g/cm³ and/or less than 0.35 g/cm³ and/or less than 0.30 g/cm³ to greater than 0 g/cm³ and/or greater than 0.05 g/cm³ and/or greater than 0.10 g/cm³ as measured according to the Micro-CT (μCT) Compacted/Compressed Fibrous Structure Article Test Method, is provided.

In yet another example of the present invention, a compacted fibrous structure article comprising a non-randomly compacted fibrous structure article, is provided.

In yet another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article such that the compacted fibrous structure article exhibits differential thickness, is provided.

In still another example of the present invention, a compacted fibrous structure article, for example a compacted fibrous structure article comprising at least one compressed portion, wherein the compacted fibrous structure article comprises a composition, for example a cleaning composition, is provided.

In even still yet another example of the present invention, a compacted fibrous structure article comprising a tab, for example a tab for reopening the compacted fibrous structure during use, is provided.

In another example of the present invention, a compacted fibrous structure article comprising a closure, for example a tab, that releasably closes the compacted fibrous structure article, for example until use of the compacted fibrous structure article, is provided.

In still yet another example of the present invention, a compacted fibrous structure article comprising a fibrous structure article comprising a plurality of pulp fibers, wherein the compacted fibrous structure article comprises a perimeter region that is adjacent to at least a portion of the compacted fibrous structure article's perimeter, wherein the compacted fibrous structure article's perimeter comprises at least one rounded corner, is provided.

In even another example of the present invention, a compacted fibrous structure article comprising a plurality of pulp fibers, wherein the compacted fibrous structure article is in a non-cylindrical compact form, is provided.

In even still another example of the present invention, a compacted fibrous structure article comprising a non-hydroentangled fibrous structure, is provided.

In even another example of the present invention, a method for making a compact fibrous structure, the method comprising the steps of folding an non-compact fibrous structure, for example at least one time and/or greater than two times and/or greater than three times, to form a folded fibrous structure, and the step of compacting the folded fibrous structure to a non-cylindrical compact form is provided.

In still even another example of the present invention, a method for making a compact fibrous structure, the method comprising the steps of non-randomly folding a non-compact fibrous structure, for example at least one time and/or greater than two times and/or greater than three times, to form a folded fibrous structure, and the step of compacting the folded fibrous structure to a non-cylindrical compact form is provided.

Accordingly, the present invention provides a compacted fibrous structure article and methods for making same that overcomes the negatives exhibited by known compacted fibrous structure articles and methods for making such known compacted fibrous structure articles.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic representation of a prior art compacted fibrous structure article;

FIG. 1B is a schematic representation of another prior art compacted fibrous structure article;

FIG. 1C is a schematic representation of another prior art compacted fibrous structure article;

FIG. 1D is a schematic representation of a prior art opening process for opening a prior art compacted fibrous structure;

FIG. 2A is a perspective view of schematic representation of an example of a compacted fibrous structure article according to the present invention;

FIG. 2B is a side view of the compacted fibrous structure article shown in FIG. 2A;

FIG. 2C is a top plan view of the compacted fibrous structure article shown in FIG. 2A;

FIG. 3 is a schematic representation of another example of a compacted fibrous structure article according to the present invention;

FIG. 4 is a schematic representation of a method for making an example of a discrete, folded fibrous structure according to the present invention;

FIG. 5 is a schematic representation of making method for making an example of a compacted fibrous structure article using the discrete, folded fibrous structure of FIG. 4;

FIG. 6 is a schematic representation of an opening process for opening an example of a compacted fibrous structure article according to the present invention;

FIG. 7 is a schematic representation of examples of tabs for use with a compacted fibrous structure article according to the present invention;

FIG. 8A is an example of a molding member suitable for use in making a fibrous structure for use in a compacted fibrous structure article according to the present invention;

FIG. 8B is another example of a molding member suitable for use in making a fibrous structure for use in a compacted fibrous structure article according to the present invention;

FIG. 8C are scanning electron microscope (SEM) images of examples of surfaces of compacted fibrous structure articles according to the present invention;

FIG. 9 is a schematic representation of a process for making a fibrous structure for use in a compacted fibrous structure article according to the present invention;

FIG. 10 is a graph of Moist Contact Area (%) to Moist−10 Low Median Depth (Moist Depth) (μm) of inventive fibrous structure articles and prior art fibrous structure articles;

FIG. 11 is a bar graph of Normalized Plate Stiffness (gf/mm-mm) of inventive compacted fibrous structure articles and prior art compacted fibrous structure articles;

FIG. 12 is a schematic representation of an example of a folding machine's components suitable for use in the process of the present invention;

FIG. 13 is a schematic representation of a set-up for use with the Moist Towel Surface Structure Test Method described herein;

FIG. 14 is a schematic representation of a Capacity Rate Tester set-up for use with the SST Absorbency Rate Test Method described herein;

FIG. 15 is a schematic top view representation of a Slip Stick Coefficient of Friction Test Method set-up;

FIG. 16 is an image of a friction sled for use in the Slip Stick Coefficient of Friction Test Method; and

FIG. 17 is a schematic side view representation of a Slip Stick Coefficient of Friction Test Method set-up.

DETAILED DESCRIPTION OF THE INVENTION Definitions

“Compacted” as used herein with reference to a compacted fibrous structure article means that a fibrous structure article, for example a sanitary tissue product, such as a paper towel sheet, has been manipulated, for example by folding and/or rolling and/or other operations that result in a decreased footprint and/or exposed/visible surface area of the fibrous structure article. Such compaction of the fibrous structure article does not lose mass, for example does not cut or remove pieces of the fibrous structure article during the compaction process. In other words, the fibrous structure article's initial footprint and/or surface area (pre-compaction) is the same as the fibrous structure article's footprint and/or surface area after reopening of the compacted fibrous structure article to its original state prior to compaction. In one example, the area of the initial/original fibrous structure article, for example a paper towel sheet, prior to compaction is greater than, for example at least 5% and/or at least 10% and/or at least 15% greater than the area of the compacted fibrous structure article. In another example, the area of the reopened fibrous structure article after reopening the compacted fibrous structure article is greater than, for example at least 5% and/or at least 10% and/or at least 15% greater than the area of the compacted fibrous structure article.

“Compressed” as used herein with reference to a compacted fibrous structure article means that the compacted fibrous structure article has been subjected to a force, for example pressure, that densifies the compacted fibrous structure article. In one example, the force, for example pressure, results in the compacted fibrous structure article exhibiting uniform density or substantially uniform density and/or uniform thickness and/or substantially uniform thickness as is present in known non-textured, non-patterned, non-embossed compacted fibrous structure articles. In another example, the force, for example pressure, results in the compacted fibrous structure article exhibiting differential density and/or differential thickness as is present in examples of compacted fibrous structure articles of the present invention.

“Sanitary tissue product” as used herein means a soft, low density (i.e. <about 0.15 g/cm³) article comprising one or more fibrous structure plies according to the present invention, wherein the sanitary tissue product is useful as a wiping implement for post-urinary and post-bowel movement cleaning (toilet tissue), for otorhinolaryngological discharges (facial tissue), and multi-functional absorbent and cleaning uses (absorbent towels). The sanitary tissue product may be convolutedly wound upon itself about a core or without a core to form a sanitary tissue product roll.

The sanitary tissue products and/or fibrous structures of the present invention may exhibit a basis weight of greater than 15 g/m² to about 120 g/m² and/or from about 15 g/m² to about 110 g/m² and/or from about 20 g/m² to about 100 g/m² and/or from about 30 to 90 g/m². In addition, the sanitary tissue products and/or fibrous structures of the present invention may exhibit a basis weight between about 40 g/m² to about 120 g/m² and/or from about 50 g/m² to about 110 g/m² and/or from about 55 g/m² to about 105 g/m² and/or from about 60 to 100 g/m².

The sanitary tissue products of the present invention may exhibit a sum of MD and CD dry tensile strength (total dry tensile) of greater than about 59 g/cm (150 g/in) and/or from about 78 g/cm to about 394 g/cm and/or from about 98 g/cm to about 335 g/cm. In addition, the sanitary tissue product of the present invention may exhibit a sum of MD and CD dry tensile strength of greater than about 196 g/cm and/or from about 196 g/cm to about 394 g/cm and/or from about 216 g/cm to about 335 g/cm and/or from about 236 g/cm to about 315 g/cm. In one example, the sanitary tissue product exhibits a sum of MD and CD dry tensile strength of less than about 394 g/cm and/or less than about 335 g/cm.

In another example, the sanitary tissue products of the present invention may exhibit a sum of MD and CD dry tensile strength (total dry tensile) of greater than about 196 g/cm and/or greater than about 236 g/cm and/or greater than about 276 g/cm and/or greater than about 315 g/cm and/or greater than about 354 g/cm and/or greater than about 394 g/cm and/or from about 315 g/cm to about 3200 g/cm and/or from about 315 g/cm to about 2700 g/cm and/or from about 325 g/cm to about 2000 g/cm and/or from about 354 g/cm to about 1181 g/cm and/or from about 354 g/cm to about 984 g/cm and/or from about 394 g/cm to about 787 g/cm. In one example, the sanitary tissue products of the present invention exhibit a total dry tensile of from about 1500 g/cm to about 2500 g/cm.

The sanitary tissue products of the present invention may exhibit an initial sum of MD and CD wet tensile strength (initial total wet tensile) of less than about 78 g/cm and/or less than about 59 g/cm and/or less than about 39 g/cm and/or less than about 29 g/cm.

The sanitary tissue products of the present invention may exhibit an initial sum of MD and CD wet tensile strength (initial total wet tensile) of greater than about 118 g/cm and/or greater than about 157 g/cm and/or greater than about 196 g/cm and/or greater than about 236 g/cm and/or greater than about 276 g/cm and/or greater than about 315 g/cm and/or greater than about 354 g/cm and/or greater than about 394 g/cm and/or from about 118 g/cm to about 1968 g/cm and/or from about 157 g/cm to about 1181 g/cm and/or from about 196 g/cm to about 984 g/cm and/or from about 196 g/cm to about 787 g/cm and/or from about 196 g/cm to about 591 g/cm.

The sanitary tissue products of the present invention may exhibit a density (based on measuring caliper at 95 g/in²) of less than about 0.60 g/cm³ and/or less than about 0.30 g/cm³ and/or less than about 0.20 g/cm³ and/or less than about 0.10 g/cm³ and/or less than about 0.07 g/cm³ and/or less than about 0.05 g/cm³ and/or from about 0.01 g/cm³ to about 0.20 g/cm³ and/or from about 0.02 g/cm³ to about 0.10 g/cm³.

The sanitary tissue product may comprise a plurality of connected, but perforated sheets of fibrous structure, that are separably dispensable from adjacent sheets.

The fibrous structures and/or sanitary tissue products of the present invention may comprise additives such as one or more compositions, for example cleaning compositions comprising surfactants, such as lathering surfactants and/or foaming surfactants, surface softening agents, for example silicones, quaternary ammonium compounds, aminosilicones, lotions, and mixtures thereof, temporary wet strength agents, permanent wet strength agents, bulk softening agents, wetting agents, latexes, especially surface-pattern-applied latexes, dry strength agents such as carboxymethylcellulose and starch, and other types of additives suitable for inclusion in and/or on sanitary tissue products and/or shave compositions and/or skin care compositions.

In one example, the sanitary tissue product and/or fibrous structure of the present invention exhibits permanent wet strength and/or comprises permanent wet strength agents. In another example, the sanitary tissue product and/or fibrous structure of the present invention comprises a temporary wet strength agent and/or is void of permanent wet strength. In one example, the sanitary tissue product and/or fibrous structure of the present invention if flushable, for example flushable via toilets into municipal sewer systems and/or septic systems, for example bath tissue void of permanent wet strength. In another example, the sanitary tissue product and/or fibrous structure article is not suitable for flushing, for example not suitable for flushing via toilets into municipal sewer systems and/or septic systems, for example paper towels and/or facial tissues exhibiting permanent wet strength.

“Fibrous structure” as used herein means a structure that comprises a plurality of fibrous elements, for example a plurality of filaments and/or fibers, such as a plurality of pulp fibers, for example wood pulp fibers. In one example, the fibrous structure may comprise a plurality of wood pulp fibers. In another example, the fibrous structure may comprise a plurality of non-wood pulp fibers, for example plant fibers, synthetic staple fibers, and mixtures thereof. In still another example, in addition to or alternative to fibers, such as pulp fibers, the fibrous structure may comprise a plurality of filaments, such as polymeric filaments, for example thermoplastic filaments such as polyolefin filaments (i.e., polypropylene filaments), such as in the form of a co-formed fibrous structure where the pulp fibers and filaments are commingled together. In one example, a fibrous structure according to the present invention means an orderly arrangement of fibrous elements, for example filaments or fibers alone or in combination with each other within a structure in order to perform a function. Non-limiting examples of fibrous structures of the present invention include paper, such as wet-laid fibrous structures, for example wet-laid paper.

Non-limiting examples of processes for making fibrous structures include known wet-laid papermaking processes, for example conventional wet-pressed papermaking processes and through-air-dried papermaking processes, and air-laid papermaking processes. Such processes typically include steps of preparing a fiber composition in the form of a suspension in a medium, either wet, more specifically aqueous medium, or dry, more specifically gaseous, i.e. with air as medium. The aqueous medium used for wet-laid processes is oftentimes referred to as a fiber slurry. The fibrous slurry is then used to deposit a plurality of fibers onto a forming wire, fabric, or belt such that an embryonic fibrous structure is formed, after which drying and/or bonding the fibers together results in a fibrous structure. Further processing the fibrous structure may be carried out such that a finished fibrous structure is formed. For example, in typical papermaking processes, the finished fibrous structure is the fibrous structure that is wound on the reel at the end of papermaking, often referred to as a parent roll, and may subsequently be converted into a finished product, e.g. a single- or multi-ply sanitary tissue product.

In one example, the fibrous structure and/or sanitary tissue product is a non-hydroentangled fibrous structure and/or sanitary tissue product.

In another example, the fibrous structure and/or sanitary tissue product is a hydroentangled fibrous structure and/or sanitary tissue product.

In one example, the fibrous structure and/or sanitary tissue product is a non-carded fibrous structure and/or sanitary tissue product.

In still another example, the fibrous structure and/or sanitary tissue product is a carded-fibrous structure.

Other non-limiting examples of processes for making example of fibrous structure according to the present invention include meltblowing processes, for example using a meltblow die, such as a knife-edge die and/or a multi-row capillary meltblow die, for example a Biax-Fiberfilm Corporation multi-row capillary meltblow die. In one example, the fibrous structure is a meltblow fibrous structure produced from a meltblow die, for example a multi-row capillary meltblow die. In another example, the fibrous structure is a co-formed fibrous structure produced by commingling a plurality of filaments produced from a multi-row capillary meltblow die with a plurality of solid additives, such as fibers, for example pulp fibers, such as wood pulp fibers and optionally an included scrim on at least one surface of the co-formed fibrous structure, wherein the scrim is produced by spinning a plurality of filaments from a meltblow die, for example a multi-row meltblow die, and collecting the spun filament directly on a surface of the co-formed fibrous structure. In addition to meltblowing processes, the fibrous structure of the present invention may be produced from a spunbonding process. In one example, the fibrous structure is a spunbond fibrous structure produced form a spunbond die. In another example, the fibrous structure comprises one or more meltblow fibrous structures and/or meltblow layers and one or more spunbond fibrous structures and/or spunbond layers and/or one or more pulp fiber fibrous structures and/or pulp fiber layers.

The fibrous structures of the present invention may be homogeneous or may be layered. If layered, the fibrous structures may comprise at least two and/or at least three and/or at least four and/or at least five layers of fiber and/or filament compositions.

In one example, the fibrous structure of the present invention consists essentially of fibers, for example pulp fibers, such as cellulosic pulp fibers and more particularly wood pulp fibers.

In another example, the fibrous structure of the present invention comprises fibers and is void of filaments.

“Co-formed fibrous structure” as used herein means that the fibrous structure comprises a mixture of at least two different materials wherein at least one of the materials comprises a filament, such as a polypropylene filament, and at least one other material, different from the first material, comprises a solid additive, such as a fiber and/or a particulate. In one example, a co-formed fibrous structure comprises solid additives, such as fibers, such as wood pulp fibers, and filaments, such as polypropylene filaments.

“Fibrous element” and/or “Fiber” and/or “Filament” as used herein means an elongate particulate having an apparent length greatly exceeding its apparent width, i.e. a length to diameter ratio of at least about 10. In one example, a “fiber” is an elongate particulate as described above that exhibits a length of less than 5.08 cm (2 in.) and a “filament” is an elongate particulate as described above that exhibits a length of greater than or equal to 5.08 cm (2 in.).

Fibers are typically considered discontinuous in nature. Non-limiting examples of fibers include pulp fibers, such as wood pulp fibers, and synthetic staple fibers such as polyester fibers.

Filaments are typically considered continuous or substantially continuous in nature. Filaments are relatively longer than fibers. Non-limiting examples of filaments include meltblown and/or spunbond filaments. Non-limiting examples of materials that can be spun into filaments include synthetic polymers including, but not limited to thermoplastic polymer filaments, such as polyesters, nylons, polyolefins such as polypropylene filaments, polyethylene filaments, and biodegradable or compostable thermoplastic fibers such as polylactic acid filaments, polyhydroxyalkanoate filaments, polyesteramide filaments, and polycaprolactone filaments. The filaments may be monocomponent or multicomponent, such as bicomponent filaments.

In one example of the present invention, “fiber” refers to papermaking fibers. Papermaking fibers useful in the present invention include cellulosic fibers commonly known as wood pulp fibers. Applicable wood pulps include chemical pulps, such as Kraft, sulfite, and sulfate pulps, as well as mechanical pulps including, for example, groundwood, thermomechanical pulp and chemically modified thermomechanical pulp. Chemical pulps, however, may be preferred since they impart a superior tactile sense of softness to tissue sheets made therefrom. Pulps derived from both deciduous trees (hereinafter, also referred to as “hardwood”) and coniferous trees (hereinafter, also referred to as “softwood”) may be utilized. The hardwood and softwood fibers can be blended, or alternatively, can be deposited in layers to provide a stratified fibrous structure. U.S. Pat. Nos. 4,300,981 and 3,994,771 are incorporated herein by reference for the purpose of disclosing layering of hardwood and softwood fibers. Also applicable to the present invention are fibers derived from recycled paper, which may contain any or all of the above categories as well as other non-fibrous materials such as fillers and adhesives used to facilitate the original papermaking.

In one example, the wood pulp fibers are selected from the group consisting of hardwood pulp fibers, softwood pulp fibers, and mixtures thereof. The hardwood pulp fibers may be selected from the group consisting of: tropical hardwood pulp fibers, northern hardwood pulp fibers, and mixtures thereof. The tropical hardwood pulp fibers may be selected from the group consisting of: eucalyptus fibers, acacia fibers, and mixtures thereof. The northern hardwood pulp fibers may be selected from the group consisting of: cedar fibers, maple fibers, and mixtures thereof.

In addition to the various wood pulp fibers, other cellulosic fibers such as cotton linters, rayon, lyocell, trichomes, seed hairs, and bagasse can be used in this invention. Other sources of cellulose in the form of fibers or capable of being spun into fibers include grasses and grain sources.

“Trichome” or “trichome fiber” as used herein means an epidermal attachment of a varying shape, structure and/or function of a non-seed portion of a plant. In one example, a trichome is an outgrowth of the epidermis of a non-seed portion of a plant. The outgrowth may extend from an epidermal cell. In one embodiment, the outgrowth is a trichome fiber. The outgrowth may be a hairlike or bristlelike outgrowth from the epidermis of a plant.

Trichome fibers are different from seed hair fibers in that they are not attached to seed portions of a plant. For example, trichome fibers, unlike seed hair fibers, are not attached to a seed or a seed pod epidermis. Cotton, kapok, milkweed, and coconut coir are non-limiting examples of seed hair fibers.

Further, trichome fibers are different from non-wood bast and/or core fibers in that they are not attached to the bast, also known as phloem, or the core, also known as xylem portions of a nonwood dicotyledonous plant stem. Non-limiting examples of plants which have been used to yield nonwood bast fibers and/or nonwood core fibers include kenaf, jute, flax, ramie and hemp.

Further trichome fibers are different from monocotyledonous plant derived fibers such as those derived from cereal straws (wheat, rye, barley, oat, etc.), stalks (corn, cotton, sorghum, Hesperaloe funifera, etc.), canes (bamboo, bagasse, etc.), grasses (esparto, lemon, sabai, switchgrass, etc), since such monocotyledonous plant derived fibers are not attached to an epidermis of a plant.

Further, trichome fibers are different from leaf fibers in that they do not originate from within the leaf structure. Sisal and abaca are sometimes liberated as leaf fibers.

Finally, trichome fibers are different from wood pulp fibers since wood pulp fibers are not outgrowths from the epidermis of a plant; namely, a tree. Wood pulp fibers rather originate from the secondary xylem portion of the tree stem.

In one example, the fibers may comprise monocotyledonous plant derived fibers such as those derived from cereal straws (wheat, rye, barley, oat, etc), stalks (corn, cotton, sorghum, Hesperaloe funifera, etc.), canes (bamboo, bagasse, etc.), grasses (esparto, lemon, sabai, switchgrass, etc) and mixtures thereof.

“Basis Weight” as used herein is the weight per unit area of a sample reported in lbs/3000 ft² or g/m² (gsm) and is measured according to the Basis Weight Test Method described herein.

“Machine Direction” or “MD” as used herein means the direction parallel to the flow of the fibrous structure through the fibrous structure making machine and/or sanitary tissue product manufacturing equipment.

“Cross Machine Direction” or “CD” as used herein means the direction parallel to the width of the fibrous structure making machine and/or sanitary tissue product manufacturing equipment and perpendicular to the machine direction.

“Ply” as used herein means an individual, integral fibrous structure.

“Plies” as used herein means two or more individual, integral fibrous structures disposed in a substantially contiguous, face-to-face relationship with one another, forming a multi-ply fibrous structure and/or multi-ply sanitary tissue product. It is also contemplated that an individual, integral fibrous structure can effectively form a multi-ply fibrous structure, for example, by being folded on itself.

“Embossed” as used herein with respect to a fibrous structure and/or sanitary tissue product means that a fibrous structure and/or sanitary tissue product has been subjected to a process which converts a smooth surfaced fibrous structure and/or sanitary tissue product to a decorative surface by replicating a design on one or more emboss rolls, which form a nip through which the fibrous structure and/or sanitary tissue product passes. Embossed does not include creping, microcreping, printing or other processes that may also impart a texture and/or decorative pattern to a fibrous structure and/or sanitary tissue product.

“Differential density”, as used herein with respect to a fibrous structure and/or fibrous structure article and/or sanitary tissue product, means a fibrous structure and/or fibrous structure article and/or sanitary tissue product comprises one or more regions of relatively low fibrous element density, which are referred to as pillow regions, and one or more regions of relatively high fibrous element density, which are referred to as knuckle regions. In one example, a fibrous structure, for example a structured fibrous structure, and/or sanitary tissue product of the present invention comprises a surface comprising a surface pattern comprising a continuous knuckle region and a plurality of discrete pillow regions that exhibit different densities, for example, one or more of the discrete pillow regions may exhibit a density that is lower than the density of the continuous knuckle region. In another example, a fibrous structure and/or sanitary tissue product of the present invention comprises a surface comprising a surface pattern comprising a continuous pillow region and a plurality of discrete knuckle regions that exhibit different densities, for example, one or more of the discrete knuckle regions may exhibit a density that is higher than the density of the continuous pillow region. In still another example, a fibrous structure and/or sanitary tissue product of the present invention comprises a surface comprising a surface pattern comprising a continuous pillow region, such as a continuous pillow network, one or more discrete knuckle regions, such as a discrete, continuous knuckle network dispersed throughout the continuous pillow network, and a one or more discrete pillow regions, such as a plurality of discrete pillows dispersed throughout the discrete, continuous knuckle network, which in turn is dispersed throughout the continuous pillow network.

Alternatively and/or in addition to, “differential density” as used herein with respect to a compacted fibrous structure article of the present invention, means that the compacted fibrous structure article comprises two or more regions and/or portions that exhibit different densities, for example densities that differ from each other by at least 1% and/or at least 2% and/or at least 3% and/or at least 4% and/or at least 5% and/or at least 6% and/or at least 7% and/or at least 8% and/or at least 9% and/or at least 10% and/or at least 15% and/or at least 20% and/or at least 30% and/or to about 90% and/or to about 80% and/or to about 70%, for example a center region and/or portion that exhibits a density less than one or more edge regions and/or portions. In one example, the compacted fibrous structure article exhibits two or more and/or three or more and/or four or more different regions or portions that exhibit different densities, for example differential density.

“Densified”, as used herein means a portion of a compacted fibrous structure article and/or fibrous structure and/or sanitary tissue product that is characterized by regions of relatively high fibrous element density (for example knuckle regions within a fibrous structure and/or sanitary tissue product).

“Non-densified”, as used herein, means a portion of a compacted fibrous structure article and/or fibrous structure and/or sanitary tissue product that exhibits a lesser density (one or more regions of relatively lower fiber density) (for example a pillow region within a fibrous structure and/or sanitary tissue product) than another portion (for example a knuckle region within a fibrous structure and/or sanitary tissue product) of the compacted fibrous structure article and/or fibrous structure and/or sanitary tissue product.

“Creped” as used herein means creped off of a Yankee dryer or other similar roll and/or fabric creped and/or belt creped. Rush transfer of a fibrous structure alone does not result in a “creped” fibrous structure or “creped” sanitary tissue product for purposes of the present invention.

“Juxtaposed” as used herein means two or more groups (of two or more discrete pillow regions) are arranged side-by-side for contrasting effect.

“Repeat unit” as used herein means a pattern unit, which is the part or section of a pattern that is repeated to create the pattern, such as the surface pattern of a fibrous structure according to the present invention. In one example, the repeat unit is defined by and/or formed by and/or consists of a group of two or more and/or three or more discrete pillow regions. In another example, the repeat unit is defined by and/or formed by and/or consists of two or more groups of two or more and/or three or more discrete pillow regions.

In one example, a repeat unit, for example a group of two or more and/or three or more discrete pillow regions is translated and/or rotated and/or reflected to form a surface pattern on a fibrous structure from the repeat unit.

In another example, a repeat unit, for example a group of two or more and/or three or more discrete pillow regions is translated and rotated to form a surface pattern on a fibrous structure from the repeat unit.

In one example, a repeat unit, for example two groups of two or more and/or three or more discrete pillow regions is translated and/or rotated and/or reflected to form a surface pattern on a fibrous structure from the repeat unit.

In another example, a repeat unit, for example two groups of two or more and/or three or more discrete pillow regions is translated and rotated to form a surface pattern on a fibrous structure from the repeat unit.

Compacted Fibrous Structure Article

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 of the present invention comprises a fibrous structure article, for example a woven and/or nonwoven fibrous structure, such as a fibrous structure comprising a plurality of fibrous elements, for example fibers, such as wood pulp fibers, that exhibits differential density as shown for example in FIG. 2B. FIG. 2B shows a first portion 30, for example a center region or portion, of the compacted fibrous structure article 10 that exhibits a lower density than at least one other portion, for example a second portion 32, for example an edge or border portion, of the compacted fibrous structure article 10. In one example, the minimum difference in density between the first portion 30 and the second portion 32 is at least 1% and/or at least 2% and/or at least 3% and/or at least 4% and/or at least 5% and/or at least 6% and/or at least 7% and/or at least 8% and/or at least 9% and/or at least 10% and/or at least 15% and/or at least 20% and/or at least 30% and/or to about 90% and/or to about 80% and/or to about 70%.

In another example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 of the present invention comprises a fibrous structure article, for example a woven and/or nonwoven fibrous structure, such as a fibrous structure comprising a plurality of fibrous elements, for example fibers, such as wood pulp fibers, that exhibits differential thickness as shown for example in FIG. 2B. FIG. 2B shows a first portion 30 of the compacted fibrous structure article 10 that exhibits a greater thickness T₁ than at least one other portion, for example a second portion 32 of the compacted fibrous structure article 10, thickness T₂. In one example, the minimum difference in thicknesses between the first portion 30, for example T₁, and the second portion 32, for example T₂, is at least 2 mm and/or at least 3 mm and/or at least 4 mm and/or at least 5 mm and/or at least 6 mm and/or at least 7 mm and/or at least 8 mm and/or at least 9 mm and/or at least 10 mm and/or to about 100 mm and/or to about 90 mm and/or to about 80 mm and/or to about 70 mm and/or to about 60 mm and/or to about 50 mm and/or to about 40 mm and/or to about 30 mm. In one example, the thickness of the first portion 30, for example T₁, is greater than about 3 mm and/or greater than about 4 mm and/or greater than about 5 mm and/or greater than about 6 mm and/or greater than about 7 mm and/or greater than about 8 mm and/or greater than about 9 mm and/or greater than about 10 mm and/or to about 110 mm and/or to about 100 mm and/or to about 80 mm and/or to about 60 mm and/or to about 50 mm and/or to about 40 mm and/or to about 30 mm. In one example, the thickness of the second portion 32, for example T₂, is greater than about 0.5 mm and/or greater than about 1 mm and/or greater than about 2 mm and/or greater than about 3 mm and/or greater than about 4 mm and/or greater than about 5 mm and/or to about 50 mm and/or to about 40 mm and/or to about 30 mm and/or to about 20 mm and/or to about 10 mm and/or to about 7 mm and/or to about 6 mm.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 of the present invention comprises a fibrous structure article, for example a woven and/or nonwoven fibrous structure, such as a fibrous structure comprising a plurality of fibrous elements, for example fibers, such as wood pulp fibers, having a first portion 30 of the compacted fibrous structure article 10 that defines at least partially a first region, for example a central region, and a second portion 32 of the compacted fibrous structure article 10 that defines at least partially a second region, for example a perimeter region that at least partially surrounds the first region, such as a perimeter region or portion that is an edge or border region or portion of the compacted fibrous structure article.

In one example, the compacted fibrous structure article comprises a perimeter region that is adjacent to at least a portion of the compacted fibrous structure article's perimeter, wherein the compacted fibrous structure article's perimeter comprises at least one rounded corner, for example two or more rounded corners and/or three or more rounded corners and/or four or more rounded corners.

In one example, the perimeter region is adjacent to 100% and/or substantially 100% of the compacted fibrous structure article's perimeter.

In one example, the compacted fibrous structure article further comprises a central region that is at least partially surrounded by the perimeter region, for example fully surrounded by the perimeter region. In one example, the central region and the perimeter region exhibit different calipers, for example the different calipers differ by at least 5% and/or at least 10% as measured according to the Caliper Test Method described herein.

In one example, the compacted fibrous structure article comprises a plurality of wood pulp fibers and/or a plurality of synthetic fibers, for example hydrophilic polymer fibers and/or polysaccharide fibers, for example polysaccharide fibers selected from the group consisting of: cellulose, cellulose derivatives, hemicellulose, hemicellulose derivatives, lignin cellulose, starch, starch derivatives and mixtures thereof. In one example, the polysaccharide fibers are selected from the group consisting of: rayon fibers, viscose fibers, and mixtures thereof. In one example, the polysaccharide fibers comprise viscose fibers.

In one example, the compacted fibrous structure article 10 of the present invention comprises a first surface 34 and an opposing second surface 36 that exhibit the same or different surface topographies, for example the second surface 36 may be substantially flat, such as without any protrusion or protrusions (not shown) and the first surface 34, like is shown in FIGS. 2A-2C may have one or more protrusions, for example in this case a large “bump”-like feature that protrudes from the first surface 34. In another example, both the first and second surfaces 34, 36 may have one or more protrusions, for example in this case each first and second surfaces 34, 36 having a large “bump”-like feature that protrudes from the each of the first and second surfaces 34, 36.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 of the present invention comprises a fibrous structure article, for example a woven and/or nonwoven fibrous structure, such as a fibrous structure comprising a plurality of fibrous elements, for example fibers, such as wood pulp fibers, having a first portion 30 of the compacted fibrous structure article 10 that comprises a first portion surface 38 that comprises a surface pattern, for example a visible surface pattern with the naked eye user, such as texture and/or a molded microscopical three-dimensional pattern and/or an emboss pattern, and a second portion 32 of the compacted fibrous structure article 10 that comprises a second portion surface 40 little to no surface pattern, for example no visible surface pattern with the naked eye of a user. Once the compacted fibrous structure article 10 has been uncompacted to its uncompacted form, then the second portion surface 40 may comprise a surface pattern, for example a visible surface pattern with the naked eye user, such as texture and/or a molded microscopical three-dimensional pattern and/or an emboss pattern, especially if the surface pattern is a molded microscopical three-dimensional pattern that has been wet molded into the fibrous structure article before the compaction process to form the compacted fibrous structure article.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 of the present invention comprises a fibrous structure article, for example a woven and/or nonwoven fibrous structure, such as a fibrous structure comprising a plurality of fibrous elements, for example fibers, such as wood pulp fibers, that exhibits differential density as shown for example in FIG. 2B. FIG. 2B shows a first portion 30 of the compacted fibrous structure article 10 that comprises an uncompressed region and a second portion 32 of the compacted fibrous structure article 10 that comprises a compressed region.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 is in a non-cylindrical compact form.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a fibrous structure article, for example a sanitary tissue product, for example a paper towel, that comprises a single- or multi-ply fibrous structure. In one example, the compacted fibrous structure article 10 comprises a single-ply fibrous structure article, for example a single-ply fibrous structure article comprising a single-ply fibrous structure comprising a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant. In another example, the compacted fibrous structure article 10 comprises a multi-ply fibrous structure article, for example a multi-ply fibrous structure article comprising a multi-ply fibrous structure comprising a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a shave composition, for example a shaving composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a skin care composition, for example a skin care composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a non-hydroentangled fibrous structure article, such as a non-hydroentangled fibrous structure article comprising a non-hydroentangled fibrous structure comprising a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a structured fibrous structure article, such as a structured fibrous structure article comprising a structured fibrous structure comprising a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a creped fibrous structure article, such as a creped fibrous structure article comprising a creped fibrous structure comprising a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C, the compacted fibrous structure article 10 comprises a structured fibrous structure article, such as a structured fibrous structure article comprising a structured fibrous structure comprising a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant.

In one example of the present invention, as shown in FIGS. 2A-2C and 3, the compacted fibrous structure article 10 comprises a tab 42, for example a tab that covers less than the entire surface of the first surface 34 of the compacted fibrous structure article 10. The tab 42 may be any shape, for example polygonal, triangular, abstract, curvilinear, arc, sinusoidal. In one example, the tab 42 functions as a closure for the compacted fibrous structure article 10, especially in the case of a compacted fibrous structure article 10 that exhibits differential density and/or differential thickness as shown in FIGS. 2A-2C. In another example, the tab 42 functions as a grasping element, for example a visible grasping element by which a user can grasp the compacted fibrous structure article during the uncompaction process to open the compacted fibrous structure article to its uncompacted form/state, especially after contacting the compacted fibrous structure article with water or another liquid.

In one example, the compacted fibrous structure article comprises a first surface and a second surface opposite the first surface such that the tab forms a part of at least one of the first and second surfaces, for example the tab is folded upon the at least one of the first and second surfaces. In one example, the tab covers less than 100% and/or less than 90% and/or less than 75% and/or less than 50% and/or greater than 5% and/or greater than 7% and/or greater than 10% and/or greater than 15% and/or greater than 20% of the at least one of the first and second surfaces. In one example, at least a portion of the tab is present in the compacted fibrous structure article's edge or border region or portion. In another example at least a portion of the tab is present in the compacted fibrous structure article's center region or portion. In another example, at least a portion of the tab is present in the compacted fibrous structure article's edge or border region or portion and at least a portion of the tab is present in the compacted fibrous structure article's center region or portion. In another example, at least a portion of the tab is present in the compacted fibrous structure article's relatively higher density region compared to other regions of the compacted fibrous structure article. In another example at least a portion of the tab is present in the compacted fibrous structure article's relatively lower density region compared to other regions of the compacted fibrous structure article. In another example, at least a portion of the tab is present in the compacted fibrous structure article's relatively higher density region and at least a portion of the tab is present in the compacted fibrous structure article's relatively lower density region. In one example, the tab exhibits an edge by which a user can grasp the tab to start the reopening process wherein the edge of the tab is present in the compacted fibrous structure article's center region or portion. In one example, the tab exhibits an edge by which a user can grasp the tab to start the reopening process wherein the edge of the tab is present in the compacted fibrous structure article's lower density region compared to other regions of the compacted fibrous structure article.

In one example, the compacted fibrous structure article's tab releasably closes the first surface to the second surface.

In one example, the compacted fibrous structure article's tab extends from one of the first and second surfaces to the other of the first and second surfaces.

In one example, the compacted fibrous structure article's tab covers at least a portion of a side of the compacted fibrous structure article.

In one example, the compacted fibrous structure article comprises a closure, for example a tab, that releasably closes the compacted fibrous structure article. In one example, the compacted fibrous structure article comprises a first surface and a second surface opposite the first surface such that the closure forms a part of at least one of the first and second surfaces, for example wherein the closure releasably closes the first surface to the second surface.

In one example, the closure extends from one of the first and second surfaces to at least the other of the first and second surfaces.

In one example, the closure covers at least a portion of a side of the compacted fibrous structure article.

Any of the examples of the compacted fibrous structure article of the present invention may comprise a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant. When a compacted fibrous structure article comprises a cleaning composition, for example a cleaning composition comprising a surfactant, such as a lathering surfactant and/or foaming surfactant, the compacted fibrous structure article and more importantly its uncompacted form/state provides a lather and/or foam to facilitate cleaning of surfaces, such as hard surfaces and/or soft surfaces, such as skin.

In one example, the compacted fibrous structure article and/or its fibrous structure article and/or its fibrous structure may comprises a rheological solid composition, for example a rheological solid composition comprising a crystallizing agent and an aqueous phase, for example wherein the crystallizing agent comprises a salt of a fatty acid containing from about 13 to about 20 carbon atoms.

Any of the examples of the compacted fibrous structure article of the present invention may comprise an ingredient selected from the group consisting of: antibacterial agents, antimicrobial agents, odor controlling agents, odor masking agents, perfumes, dry soap particles, surfactants, for example lathering and/or foaming surfactants, surface softening agents, lotions, polishing agents, dusting agents, and mixtures thereof.

In one example, the compacted fibrous structure article comprises two or more incompatible ingredients, for example that are separated from one another in the dry state, but then come into contact with each other in the wet state, for example during use of the compacted fibrous structure article. For example, the compacted fibrous structure article comprises a first composition comprising a surfactant, such as a foaming surfactant, and a second composition comprising a perfume that are present in the compacted fibrous structure article in different locations when dry, but then may come into contact with each other when wet, for example during use of the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article comprises a single-ply fibrous structure article comprising a tab. In another example of the present invention, the compacted fibrous structure article comprises a multi-ply fibrous structure article comprising a tab.

In one example of the present invention, the compacted fibrous structure article comprises a closure that releasably closes the compacted fibrous structure article. In one example, such as closure does not cover a sufficient amount of a surface of the compacted fibrous structure article to function as a tab as discussed above, but does function to close a compacted fibrous structure article, for example a compacted fibrous structure article comprising a folded fibrous structure article in a similar fashion with respect to closing that the tab does.

In one example of the present invention, the compacted fibrous structure article may comprise embossing to signal use.

In one example of the present invention, the compacted fibrous structure article may comprise a perfume and/or scent.

In one example of the present invention, the compacted fibrous structure article is dry-to-the-touch and optionally is water-activated prior to use, for example prior to use of the uncompacted form/state of the compacted fibrous structure article. In one example, the uncompacted form/state of the compacted fibrous structure article is used in a wet state, for example the uncompacted form/state of the compacted fibrous structure article is wet, at least wet enough to generate lather and/or foam, when a cleaning composition comprising a lathering surfactant and/or foam is present, and/or saturated with water.

In one example of the present invention, the compacted fibrous structure article and/or fibrous structure article and/or fibrous structure used to make the compacted fibrous structure article and fibrous structure article may comprise print, for example logos and/or trademarks, and/or graphics comprising ink and/or laser imparted features.

In one example of the present invention, the tab, when present on the compacted fibrous structure article, may comprise print, for example logos and/or trademarks, and/or graphics comprising ink and/or laser imparted features and/or emboss and/or shaped edge that signals the presence and location of the tab.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a structured fibrous structure article comprising a structured fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a structured fibrous structure article comprising a structured fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises an embossed fibrous structure article comprising an embossed fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises an embossed fibrous structure article comprising an embossed fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a molded microscopical three-dimensional patterned fibrous structure article, for example a wet-molded microscopical three-dimensional patterned fibrous structure, comprising a molded microscopical three-dimensional patterned fibrous structure, for example a wet-molded microscopical three-dimensional patterned fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a molded microscopical three-dimensional patterned fibrous structure article, for example a wet-molded microscopical three-dimensional patterned fibrous structure, comprising a molded microscopical three-dimensional patterned fibrous structure, for example a wet-molded microscopical three-dimensional patterned fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a textured fibrous structure article comprising a textured fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a textured fibrous structure article comprising a textured fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a printed and/or laser-etched fibrous structure article comprising a printed and/or laser-etched fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a printed and/or laser-etched fibrous structure article comprising a printed and/or laser-etched fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a multi-ply fibrous structure article comprising a multi-ply fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a multi-ply fibrous structure article comprising a multi-ply fibrous structure, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a tab, for example a grasping element for opening the compacted fibrous structure article, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a tab, for example a grasping element for opening the compacted fibrous structure article, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a folded fibrous structure article, for example a fibrous structure article comprising two or more and/or three or more and/or four or more and/or five or more folds, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a folded fibrous structure article, for example a fibrous structure article comprising two or more and/or three or more and/or four or more and/or five or more folds, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a non-rolled fibrous structure article, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform density throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a non-rolled fibrous structure article, wherein the compacted fibrous structure article exhibits a uniform or substantially uniform thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a folded fibrous structure article, for example a fibrous structure article comprising two or more and/or three or more and/or four or more and/or five or more folds, wherein the compacted fibrous structure article exhibits a differential density.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a folded fibrous structure article, for example a fibrous structure article comprising two or more and/or three or more and/or four or more and/or five or more folds, wherein the compacted fibrous structure article exhibits a differential thickness throughout the compacted fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a rolled and then folded fibrous structure article.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a non-rolled fibrous structure article, wherein the compacted fibrous structure article exhibits a differential density.

In one example of the present invention, the compacted fibrous structure article of the present invention comprises a non-rolled fibrous structure article, wherein the compacted fibrous structure article exhibits a differential thickness.

In one example, an array, such as a product array on a retail shelf and/or online and/or in a retail store may comprise one or more compacted fibrous structure articles, for example a compacted paper towel, and one or more non-compacted fibrous structure articles, for example a non-compacted paper towel, for example in a roll format containing one or more rolls within a package, such as a biodegradable, compostable, recyclable, or film package rather than in a durable container, such as a canister or refill bag containing a plurality of compacted fibrous structure articles, wherein the compacted fibrous structure articles and non-compacted fibrous structure articles are manufactured by the same company and/or sold under the same brand name and/or trademark.

In one example, the compacted fibrous structure article of the present invention may be of any size and/or shape and/or dimensions (width, length, height), for example the compacted fibrous structure article of the present invention may be of any geometric shape, such as polygonal, circular, or non-polygonal, and may have rounded corners, and/or for example the compacted fibrous structure article may have dimensions of less than 200 mm and/or less than 150 mm and/or less than 100 mm and/or less than 90 mm and/or more than 10 mm and/or more than 20 mm and/or more than 30 mm and/or more than 40 mm and/or from about 50 mm to about 70 mm in width and/or length and/or height.

In one example, the compacted fibrous structure article remains strong when wet and/or exhibits improved softness when wet.

Table 1 below shows Average Overall Densities, Center Densities, Minimum Edge Densities and Maximum Edge Densities of examples of commercially available compressed fibrous structure articles.

TABLE 1 Average Overall Center Min Edge Max Edge Density Density Density Density Sample Shape (g/cm³) (g/cm³) (g/cm³) (g/cm³) YUMMAYEE Cylinder 0.84 0.84 0.80 0.89 (mini-rayon disposable compressed towel) Dimora Cylinder 0.93 0.93 0.88 0.92 (cotton compressed towel) PacknWipe Cylinder 0.82 0.82 0.74 0.84 (disposable compressed towel) PacknWipe Cylinder 0.92 0.92 0.91 0.94 (disposable compressed multi-use towel)

Process for Making the Compacted Fibrous Structure Article

The compacted fibrous structure articles of the present invention may be made by any suitable process known in the art so long as the compacted fibrous structure articles are novel as described herein.

In one example as shown in FIGS. 4 and 5, a process 44 for making a compacted fibrous structure article 10 according to the present invention may comprise providing a fibrous structure 46 according to the present invention, for example by unwinding a roll 48 of the fibrous structure 46. The fibrous structure 46 may be pre-treated with a composition 50, for example a cleaning composition, prior to being unwound in this process shown in FIG. 4 and/or may be contacted and/or impregnated with a composition 50, for example a cleaning composition by spraying, dipping, gravure roll printing, slot coating, or otherwise depositing the composition 50, which may include any of the ingredients described herein for treating a fibrous structure 46 including, but not limited to surface softening agents, surfactants, perfumes. In one example, the composition 50 is a cleaning composition comprising one or more surfactants, for example one or more lathering surfactants and/or one or more foaming surfactants. The composition 50 may be applied via a composition source 52, such as spray nozzle, a slot coater, a gravure roll printing roll, and the like to produce a treated fibrous structure 54. In one example, the composition 50 is applied to one or more portions of the fibrous structure 46 that is not exposed to further processing machinery, for example is applied to a portion of the fibrous structure 46 that is covered by a flap created during the subsequent C-folding step. In one example, two or more incompatible ingredients may be applied to portions of the fibrous structure 46 such that the incompatible ingredients are separated from each other and don't come into contact with each other until wet, for example during use of the resulting compacted fibrous structure article 10.

After treating with the composition 50, the treated fibrous structure 54 may be dried, if necessary, before proceeding to the next operation, which is an initial folding operation 56 that folds the fibrous structure 46 or treated fibrous structure 54, if it has been treated with a composition 50, for example folds the fibrous structure 46 into a C-fold. The folded fibrous structure 58 is then cut into discrete folded fibrous structures 60 by a cutting operation 62, such as a saw and/or knife, such as a rotary knife. These discrete folded fibrous structures 60 when unfolded are referred to as fibrous structure articles 60, for example sanitary tissue products, such as paper towels, of the present invention.

As shown in FIG. 5, a fibrous structure article 60 (discrete folded fibrous structure 60) produced from the process 44 shown in FIG. 4 is then folded one time about its axis A in a V-fold to produce a V-folded fibrous structure article 64. The V-folded fibrous structure article 64 is then ready for a portion to be folded upon itself one or more times and/or two or more times and/or three or more times and/or four or more times and/or five or more times along its axis A to produce a folded-up fibrous structure article 66 ensuring that a portion of the V-folded fibrous structure article 64 extends past the folded portion(s) of the folded-up fibrous structure article 66 such that a tab portion 68 is formed. Once the desired number of folds of the V-folded fibrous structure article 64 have been formed in the folded-up fibrous structure article 66, the tab portion 68 is then folded over upon the folded-up fibrous structure article 66 such that the tab portion 68 closes the folded-up fibrous structure article 66 to produce a precursor compacted fibrous structure article 70 have a closure formed by the tab portion 68 and the a portion of the folded-up fibrous structure article 66. In one example, the folded-up fibrous structure article 66 is such that when the tab portion 68 closes the folded-up fibrous structure article 66, at least a portion of the closure formed comprises less folded-up fibrous structure article 66, for example less plies and/or less basis weight, than other parts of the precursor compacted fibrous structure article 70. In one example, the tab portion 68 exhibits a minimal thickness and/or minimal layers and/or minimal material relative to the remaining fold-up fibrous structure article 66.

Next, the precursor compacted fibrous structure article 70 is then subjected to a force, for example pressure, for example from about 10,000 to about 50,000 and/or from about 20,000 to about 40,000 and/or about 30,000 pounds of force and/or a pressure, for example from about 3,000 to about 30,000 and/or from about 5,000 to about 25,000 and/or from about 7,500 to about 20,000 psi, such as after being placed into a mold and piston arrangement 72 to compress at least a portion, for example a portion of the precursor compacted fibrous structure article 70 such that the compressed and/or higher density and/or lower thickness portion of the resulting compacted fibrous structure article 10 according to the present invention is produced and therefore the compacted fibrous structure article 10 itself is produced.

In one example, the compression step with the mold and piston 72 is designed to create rounded corners in the compacted fibrous structure article 10 that aids and/or provides the ability of the compacted fibrous structure article 10 from uncompacting prematurely, such as uncompacting prior to use, for example prior to contacting the compacted fibrous structure article 10 with water.

In one example, the compression step creates one or more different shapes and/or designs and/or letters in the resulting compacted fibrous structure article.

In one example, the compacted fibrous structure articles of the present invention are made by a close-coupled and/or direct-coupled process where two or more and/or three or more and/or four or more and/or five or more unit operations, such as 1) unwinding a fibrous structure, 2) pre-treating/applying a composition to the fibrous structure, 3) drying, if necessary, 4) initial folding, for example C-folding, 5) cutting, 6) second folding, for example V-folding, 7) folding upon itself one or more times, for example two or more time, for example in a folding machine, 8) compressing, for example by a press, for example with a mold, and 9) expelling the compacted fibrous structure article from unit operation 8. In one example, unit operations 1-6 (including 3 if necessary) and the unit operation 7, for example the folding machine, are close-coupled or direct-coupled. In another example, unit operations 7, for example the folding machine, and 8, for example the press and mold, are close-coupled or direct-coupled.

In one example, the folds, including the fold that forms the tab, of the compacted fibrous structure article may be manually generated and/or machine-generated. In one example, one or more folds of the compacted fibrous structure article are machine-generated, such as via a folding machine. In one example, the tab of the compacted fibrous structure article is a machine-generated tab.

In one example, the compacted fibrous structure article is void of a composition, for example a cleaning composition or other ingredients that are applied and/or deposited onto or into the fibrous structure of the compacted fibrous structure article.

Method for Using the Compacted Fibrous Structure Article

As shown in FIG. 6, an example of a process 74 for using a compacted fibrous structure article 10, for example a compacted fibrous structure article 10 comprising a tab 42, comprises the steps of contacting the compacted fibrous structure article 10 with water 12, for example from a faucet 14, such that the compacted fibrous structure article 10 the tab 42 of the compacted fibrous structure article 10 becomes more accessible for grasping by a user's hand 22. In addition, the contact and continued contact by the water 12 may loosen the compressed and/or higher density and/or lower thickness areas, for example the second portion 32. Further, the contact and continued contact by the water 12 may cause any molded microscopical three-dimensional pattern, especially wet-molded microscopical three-dimensional pattern to become visible again after being compressed and/or densified to a state where the molded microscopical three-dimensional pattern was not visible in the compacted fibrous structure article. As the user grasps the tab 42 the compacted fibrous structure article 10 may begin to unfold from its folded, compacted state. If needed, a user can assist with the unfolding by manually assisting the unfolding and/or shaking the unfolding fibrous structure article 76. Once the unfolded fibrous structure article 76 has reached its uncompacted form/state; namely, its fibrous structure article 60 (discrete folded fibrous structure 60) then the discrete folded fibrous structure 60 may be fully unfolded to is uncompacted fibrous structure article 28, for example a sanitary tissue product, such as a paper towel. At this stage, the water 12 has had a chance to activate any cleaning composition comprising a surfactant, such as a lathering surfactant and/or a foaming surfactant, that may be present in and/or on the uncompacted fibrous structure article 28 such that the uncompacted fibrous structure article 28 may be used for cleaning of surfaces, hard and/or soft.

In one example, the compacted fibrous structure article 10 exhibits reopenability from its non-cylindrical compact form to expand in size and/or area.

In one example, the tab 42 of the compacted fibrous structure article 10 may comprise various shapes, designs, graphics, logos, words, print, texture, emboss, patterns as shown FIG. 7.

Composition

In one example of the present invention, the compacted fibrous structure article may comprise a composition, for example a cleaning composition and/or shave composition and/or skin care composition, such as a composition comprising one or more surfactants, such as a dry-to-the-touch cleaning and/or shave and/or skin care composition. In one example the composition is a cleaning composition that comprises a paste, for example a surfactant paste, such as a surfactant paste composition.

“Paste” as used herein means a material having a semi-solid form and/or comprising less than about 60% by weight of water. The paste may have a viscosity of 2000 centipoise (cps) or more.

“Surfactant paste” as used herein means a paste comprising one or more surfactants such as an anionic surfactant, amphoteric surfactant, cationic surfactant. In one example, the surfactant paste comprises an anionic surfactant, such as alkyl ethoxy sulfate surfactant, and/or an amphoteric surfactant, such as amine oxide surfactant, that is in a flowable solid state that does not continuously change its shape when subjected to a given yield stress. In one example, the surfactant paste exhibits a viscosity of 2000 cps or more.

Even though the addition of the polyhydric alcohol reduces the viscosity of the surfactant paste, it does not change the structure of the surfactant paste, in other words, it does not convert the surfactant paste into an aqueous solution of surfactants. The use of the polyhydric alcohol to reduce the viscosity of the surfactant paste avoids the negatives associated with using water to dilute the surfactant paste. The addition of water to the surfactant paste creates a random crystal pattern within the surfactant paste, creates a high water content surfactant paste that requires drying when applied to a dry substrate, and/or creates an undesirable middle phase. Surfactant mesophases are lyotropic, i.e., their structure is determined by specific interactions between the surfactant molecules. When the surfactant concentration in aqueous solution exceeds ˜10% by weight, micelle-micelle interactions become significant and the simple spherical structures generally undergo conversion first to infinite cylinders and then to multi-bilayers. The middle phase consists of surfactant molecules grouped into rod-like clusters of indefinite length that are arranged in a hexagonal packing arrangement comprising typically an oil-core, where the lipophilic groups form the core and hydrophilic groups lie on the surface; it exhibits optical birefringence (opalescence). Most surfactant/water systems are of this type. In the viscous isotropic phase, the molecules pack in spheres that then assemble into a face-centered or body-centered cubic lattice structure. A mesophase is an in-between, or intermediate, phase that exhibits certain aspects of both solid and liquid states while also possessing properties that are not found in either solids or liquids. For example, it has characteristic of crystals ((birefringence) and yet can flow like a liquid (liquid crystal).

“Surfactant paste composition” as used herein means a composition comprising a surfactant paste and one or more non-water viscosity reducing agents. In one example, the surfactant paste composition comprises a polyhydric alcohol, for example polyethylene glycol, such as a PEG that exhibits a molecular weight of less than 500 and/or 400 or less and/or 300 or less and/or greater than 100 and/or about 200 or more. The addition of a polyhydric alcohol decreases the viscosity of the surfactant paste, which is typically around 2000 or more cps to less than 1000 cps and/or to less than 700 cps and/or to less than 500 cps to about 400 cps. In one example, the surfactant paste composition exhibits a viscosity of from about 50 to about 400 cps and/or from about 100 to about 400 cps. The surfactant paste compositions of the present invention do not include surfactant pastes that have been dried down by reducing the level of water/moisture in the pastes to less than 30% by weight of free water without adding a non-water viscosity reducing agent, for example a sufficient amount of a non-water viscosity reducing agent such that the viscosity falls to less than 1000 cps, because simply reducing the water level of the surfactant pastes creates a low moisture, high viscosity (greater than 1000 cps and/or greater than 1500 cps and/or greater than 2000 cps) surfactant paste that resists penetration into a fibrous structure.

Even though the addition of the polyhydric alcohol reduces the viscosity of the surfactant paste, it does not change the structure of the surfactant paste, in other words, it does not convert the surfactant paste into an aqueous solution of surfactants. The use of the polyhydric alcohol to reduce the viscosity of the surfactant paste avoids the negatives associated with using water to dilute the surfactant paste. The addition of water to the surfactant paste creates a random crystal pattern within the surfactant paste, creates a high water content surfactant paste that requires drying when applied to a dry substrate, and/or creates an undesirable middle phase. Surfactant mesophases are lyotropic, i.e., their structure is determined by specific interactions between the surfactant molecules. When the surfactant concentration in aqueous solution exceeds ˜10% by weight, micelle-micelle interactions become significant and the simple spherical structures generally undergo conversion first to infinite cylinders and then to multi-bilayers. The middle phase consists of surfactant molecules grouped into rod-like clusters of indefinite length that are arranged in a hexagonal packing arrangement comprising typically an oil-core, where the lipophilic groups form the core and hydrophilic groups lie on the surface; it exhibits optical birefringence (opalescence). Most surfactant/water systems are of this type. In the viscous isotropic phase, the molecules pack in spheres that then assemble into a face-centered or body-centered cubic lattice structure. A mesophase is an in-between, or intermediate, phase that exhibits certain aspects of both solid and liquid states while also possessing properties that are not found in either solids or liquids. For example, it has characteristic of crystals ((birefringence) and yet can flow like a liquid (liquid crystal).

“Aqueous solution of surfactants” as used herein and known in the art is a high water content composition comprising one or more surfactants. The aqueous solution of surfactants results from the addition of water to a surfactant paste that converts the structure of the surfactant paste into an aqueous solution of surfactants such that a paste no longer exists. Clearly this is different from adding a polyhydric alcohol, such as PEG 200, to a surfactant paste that does not result in the conversion of the structure of the surfactant paste (the structure of the surfactant paste is retained) into an aqueous solution of surfactants.

“Dry-to-the-touch” as used herein means a compacted fibrous structure article is substantially free of liquids such that it does not feel damp or wet prior to being subjected to water or other liquids. In one non-limiting example, a dry-to-the-touch fibrous structure has a water content of less than about 60%, or less than about 50%, or less than about 40%. The fibrous structures (e.g., sanitary tissue products) of the present invention remain dry-to-the-touch until they are moistened with water or other liquids.

a. Surfactant Paste Composition

The surfactant paste composition of the present invention is not an aqueous solution of surfactants nor is it a low moisture, high viscosity (greater than 2000 cps) surfactant paste. It is rather a surfactant paste composition comprising a surfactant paste and one or more non-water viscosity reducing agents such that the surfactant paste composition exhibits a viscosity of less than 1000 cps. In one example, the surfactant paste composition is a surfactant paste according to the present invention that has been diluted with a non-water viscosity reducing agent, such as a polyhydroxy compound and/or mono and/or poly alcohols, such that the viscosity of the resulting surfactant paste composition is less than 1000 cps and/or less than 700 cps and/or less than 500 cps.

The surfactant paste composition of the present invention comprises one or more surfactants, for example one or more anionic surfactants, one or more amphoteric surfactants, one or more nonionic surfactants, and/or one or more cationic surfactants and one or more non-water viscosity reducing agents. In one example, the surfactant paste composition comprises an anionic surfactant, for example an alkyl ethoxy sulfate, such as AE_(0.6)S, and an amphoteric surfactant, for example amine oxide. In addition to the anionic surfactant and amphoteric surfactant, the surfactant paste composition comprises one or more non-water viscosity reducing agents. In one non-limiting example, the surfactant paste composition comprises two or more surfactants. Suitable surfactants, discussed below, include anionic surfactants (such as sulfate surfactants, sulfonate surfactants), nonionic surfactants, zwitterionic surfactants, amphotheric surfactants or combinations thereof.

The surfactants present in the surfactant paste composition of the present invention may include sulfate surfactants, for example alkyl ethoxy sulfate surfactants, sulfonate surfactants, for example alkyl benzene sulfonate surfactants, amphoteric surfactants, for example amine oxide surfactants, and nonionic surfactants, for example alcohol alkoxylated surfactants.

In one example, the surfactant paste composition of the present invention exhibits no crystal aggregation as measured according to the Crystallinity Test Method described herein. In another example, the surfactant paste composition of the present invention exhibits a different type and/or different amount of crystallinity compared to aqueous solutions of surfactants as measured according to the Crystallinity Test Method described herein. In still another example, the surfactant paste composition of the present invention exhibits no birefringence as measured according to the Crystallinity Test Method described herein.

In addition to the surfactants and the non-water viscosity reducing agents, the surfactant paste composition of the present invention may include additional amounts of surfactants (additional amounts relative to the surfactant paste from which the surfactant paste composition is made), for example additional amphoteric surfactants, such as amine oxide, and/or additional anionic surfactants, such as alkyl sulfonated surfactants. In one example, the surfactant paste composition comprises greater than 1% and/or greater than 5% and/or greater than 10% and/or less than 30% and/or less than 20% and/or less than 15% by weight of the additional surfactants. In one example, the surfactant paste composition comprises greater than 1% and/or greater than 3% and/or greater than 5% and/or less than 20% and/or less than 15% and/or less than 10% and/or less than 7% by weight of an additional amphoteric surfactant, for example amine oxide. In another example, the surfactant paste composition comprises greater than 5% and/or greater than 10% and/or less than 20% and/or less than 15% by weight of an additional anionic surfactant, such as sodium alkyl ethoxylated fatty alcohol sulfate, for example sodium laureth sulfate (C₁₀-C₁₆).

i. Sulfate Surfactants

Suitable sulfate surfactants for use herein include water-soluble salts of C₈-C₁₈ alkyl or hydroxyalkyl, sulfate and/or ether sulfate. Suitable counterions include alkali metal cation or ammonium or substituted ammonium, or sodium.

The sulfate surfactants may be selected from C₈-C₁₈ primary, branched chain and random alkyl sulfates (AS); C₈-C₁₈ secondary (2,3) alkyl sulfates; C₈-C₁₈ alkyl alkoxy sulfates (AExS) wherein x may be from 1-30 in which the alkoxy group could be selected from ethoxy, propoxy, butoxy or even higher alkoxy groups and mixtures thereof.

Alkyl sulfates and alkyl alkoxy sulfates are commercially available with a variety of chain lengths, ethoxylation and branching degrees, examples are those based on NEODOL® alcohols available from Shell Chemicals, LIAL®—ISALCHEM® and SAFOL® available from Sasol, and/or natural alcohols available from The Procter & Gamble Chemicals Company.

In an embodiment, the cleaning composition may comprise an anionic surfactant having at least 50%, or at least 60% or at least 70% of a sulfate surfactant by weight of the anionic surfactant. In one non-limiting example, the sulfate surfactant is selected from the group consisting of alkyl sulfate, alkyl ethoxy sulfates and mixtures thereof. In a further embodiment, the anionic surfactant has a degree of ethoxylation of from about 0.2 to about 3, or from about 0.3 to about 2, or from about 0.4 to about 1.5, or about 0.4 to about 1. In yet another non-limiting example, the anionic surfactant has a level of branching of from about 5% to about 40%, or from about 10% to 35%, or from about 20% to about 30%.

ii. Sulfonate Surfactants

Suitable sulfonate surfactants for use herein include water-soluble salts of C₈-C₁₈ alkyl or hydroxyalkyl sulfonates; C₁₁-C₁₈ alkyl benzene sulfonates (LAS), modified alkylbenzene sulfonate (MLAS) as discussed in WO 99/05243, WO 99/05242, WO 99/05244, WO 99/05082, WO 99/05084, WO 99/05241, WO 99/07656, WO 00/23549, and WO 00/23548; methyl ester sulfonate (MES); and alpha-olefin sulfonate (AOS). Those also include the paraffin sulfonates may be monosulfonates and/or disulfonates, obtained by sulphonating paraffins of 10 to 20 carbon atoms. The sulfonate surfactants also include the alkyl glyceryl sulfonate surfactants.

iii. Amphoteric Surfactant

Suitable amphoteric surfactants include amine oxides and betaines, including amine oxides.

Suitable amine oxides are alkyl dimethyl amine oxide or alkyl amido propyl dimethyl amine oxide. Amine oxide may have a linear or mid-branched alkyl moiety. Typical linear amine oxides include water-soluble amine oxides containing one C₈₋₁₈ alkyl moiety and two moieties selected from the group consisting of C₁₋₃ alkyl groups and C₁₋₃ hydroxyalkyl groups. In an embodiment, amine oxide is characterized by the formula R1-N(R2)(R3)O wherein R1 is a C₈₋₁₈ alkyl and R2 and R3 are selected from the group consisting of methyl, ethyl, propyl, isopropyl, 2-hydroxethyl, 2-hydroxypropyl and 3-hydroxypropyl. The linear amine oxide surfactants in particular may include linear C₁₀-C₁₈ alkyl dimethyl amine oxides and linear C₈-C₁₂ alkoxy ethyl dihydroxy ethyl amine oxides. As used herein “mid-branched” means that the amine oxide has one alkyl moiety having n1 carbon atoms with one alkyl branch on the alkyl moiety having n2 carbon atoms. The alkyl branch is located on the a carbon from the nitrogen on the alkyl moiety. This type of branching for the amine oxide is also known in the art as an internal amine oxide. The total sum of n1 and n2 is from 10 to 24 carbon atoms, or from 12 to 20, and or from 10 to 16. The number of carbon atoms for the one alkyl moiety (n1) should be approximately the same number of carbon atoms as the one alkyl branch (n2) such that the one alkyl moiety and the one alkyl branch are symmetric. As used herein “symmetric” means that |n1−n2| is less than or equal to 5, or equal to 4, and/or from 0 to 4 carbon atoms in at least 50 wt %, or at least 75 wt % to 100 wt % of the mid-branched amine oxides for use herein.

The amine oxide may further comprise two moieties, independently selected from a C₁₋₃ alkyl, a C₁₋₃ hydroxyalkyl group, or a polyethylene oxide group containing an average of from about 1 to about 3 ethylene oxide groups. The two moieties may be selected from a C₁₋₃ alkyl, or both may be selected as a C₁ alkyl.

iv. Nonionic Surfactants

The surfactant paste composition of the present invention may further comprise a nonionic surfactant, such as an alcohol alkoxylated. Suitable nonionic surfactants include the condensation products of aliphatic alcohols with from 1 to 25 moles of ethylene oxide. The alkyl chain of the aliphatic alcohol can either be straight or branched, primary or secondary, and generally contains from 8 to 22 carbon atoms. One non-limiting example of suitable nonionic surfactants are the condensation products of alcohols having an alkyl group containing from 10 to 18 carbon atoms, or from 10 to 15 carbon atoms with from 2 to 18 moles, or 2 to 15 moles, or 5-12 moles of ethylene oxide per mole of alcohol.

b. Anionic to Amphoteric Ratio

The anionic and amphoteric surfactants may be present in the surfactant paste composition and/or the surfactant paste from which the surfactant paste composition is made at a weight ratio of from about 1:1 to about 8.5:1, or at a ratio of at least 1:1 and/or greater than 1:1 and/or greater than 1.5:1 and/or greater than 2:1 to less than 6:1 and/or less than 5:1 and/or less than 4.5:1.

c. Non-Water Viscosity Reducing Agents

The surfactant paste composition of the present invention comprises one or more non-water viscosity reducing agents. In one example, the surfactant paste composition comprises a sufficient amount of one or more non-water viscosity reducing agents such that the viscosity of the surfactant paste is reduced by the non-water viscosity reducing agents to produce a viscosity of less than 1000 cps for the resulting surfactant paste composition. In one example, the surfactant paste composition comprises greater than about 10% by weight of one or more non-water viscosity reducing agents. In another example, the surfactant paste composition comprises less than about 70% by weight of one or more non-water viscosity reducing agents. In still another example, the surfactant paste composition comprises from about 14% to about 50% and/or from about 15% to about 40% and/or from about 20% to about 30% by weight of one or more non-water viscosity reducing agents.

Non-limiting examples of suitable non-water viscosity reducing agents include polyhydroxy compounds, such as polyhydric alcohols, polyethylene glycol, mono-alcohols, di-alcohols, and mixtures thereof. In one example, the non-water viscosity reducing agent comprises a polyhydric alcohol, for example polyethylene glycol, such as PEG, for example PEG having a molecular weight of less than 500 g/mol and/or 400 g/mol or less and/or 300 g/mol or less and/or greater than 100 g/mol and/or about 200 g/mol or more. In one example, the non-water viscosity reducing agent is PEG 200. In another example, the surfactant paste composition exhibits a viscosity of less than 1000 and/or less than 500 and/or from about 400 to about 50 cps and/or from about 400 to about 100 cps and/or from about 400 to about 200 cps and/or about 400 cps.

d. Surfactant Paste

The surfactant paste of the present invention comprises one or more surfactants described herein that ultimately make up the surfactant paste composition of the present invention, for example one or more anionic surfactants, one or more amphoteric surfactants, one or more nonionic surfactants, and/or one or more cationic surfactants. In one example, the surfactant paste comprises an anionic surfactant, for example an alkyl ethoxy sulfate, such as AE_(0.6)S, and an amphoteric surfactant, for example amine oxide. The surfactants present in the surfactant paste of the present invention may include sulfate surfactants, for example alkyl ethoxy sulfate surfactants, sulfonate surfactants, for example alkyl benzene sulfonate surfactants, amphoteric surfactants, for example amine oxide surfactants, and nonionic surfactants, for example alcohol alkoxylated surfactants.

In one example, the surfactant paste comprises greater than 10% and/or greater than 20% and/or greater than 30% and/or less than 70% and/or less than 60% and/or less than 50% by weight of anionic surfactants, for example sodium alkyl ethoxylated fatty alcohol sulfate. In another example, the surfactant paste comprises from about 30% to about 40% by weight of anionic surfactants, for example sodium alkyl ethoxylated fatty alcohol sulfate.

In another example, the surfactant paste comprises greater than 3% and/or greater than 5% and/or greater than 10% and/or less than 50% and/or less than 40% and/or less than 30% by weight of amphoteric surfactants, for example amine oxide, such as alkyldimethylamine oxide. In another example, the surfactant paste comprises from about 10% to about 20% by weight of amphoteric surfactants, for example amine oxide, such as alkyldimethylamine oxide.

In still another example, the surfactant paste comprises less than 5% and/or less than 3% and/or less than 2% to 0% and/or to about 0% and/or to about 0.05% and/or to about 0.1% and/or to about 1% of nonionic surfactants.

In yet another example, the surfactant paste may be void of cationic surfactants.

In still another example, the surfactant paste comprises greater than 10% and/or greater than 20% and/or greater than 30% and/or less than 70% and/or less than 60% and/or less than 50% by weight of anionic surfactants, for example sodium alkyl ethoxylated fatty alcohol sulfate, and greater than 3% and/or greater than 5% and/or greater than 10% and/or less than 50% and/or less than 40% and/or less than 30% by weight of amphoteric surfactants, for example amine oxide, such as alkyldimethylamine oxide. In another example, the surfactant paste comprises from about 30% to about 40% by weight of anionic surfactants, for example sodium alkyl ethoxylated fatty alcohol sulfate, and from about 10% to about 20% by weight of amphoteric surfactants, for example amine oxide, such as alkyldimethylamine oxide.

One non-limiting example of a surfactant paste suitable for use in the present invention is DUPONOL EP Surfactant, commercially available from DuPont.

e. Method for Making a Surfactant Paste Composition

In one embodiment, a method for making a surfactant paste composition of the present invention comprises providing a surfactant paste comprising one or more surfactants. The surfactant paste exhibit a viscosity of 2000 cps or more. In one non-limiting example, the surfactant paste exhibits a viscosity of more than 5000 cps. The method further comprises the step of adding a non-water viscosity reducing agent to the surfactant paste such that the viscosity of the surfactant paste is reduced to less than 1000 cps and/or less than 700 cps and/or less than 500 cps and/or about 400 cps. In one non-limiting example, one or more of the non-water viscosity reducing agents comprises a polyhydroxy compound, such as polyethylene glycol. The polyhydroxy compound may have a molecular weight of 200 or less. Further, in one non-limiting example, the polyhydroxy compound may be provided at a viscosity of about 50 cps. In one example, the polyhydroxy compound forms the continuous phase of the surfactant paste composition.

The method may further include adding one or more additional surfactants to the surfactant paste, before, during, and/or after the addition of the one or more non-water viscosity reducing agents. The additional surfactants, when added, may be much less viscous than the surfactant paste. For example, the additional surfactants may be less than about 10% as viscous as the surfactant paste and/or less than about 1% and/or less than about 0.1% and/or less than about 0.05%. In one non-limiting example, the additional surfactants may exhibit a viscosity of about 10 cps. In another non-limiting example, the additional surfactants may comprise amine oxide. In yet another non-limiting example, the additional surfactants may comprise a zwitterionic surfactant, such as zwitterionic betaine C₁₂.

The method may include a mixing step or a series of mixing steps, wherein the surfactant paste, additional surfactants and non-water viscosity reducing agents are combined. In an embodiment, the surfactant paste, additional surfactants and non-water viscosity reducing agents are combined such that the viscosity of the surfactant paste composition (i.e., the mixture of all 3 components) is less than 1000 cps and/or less than 700 cps and/or less than 500 cps and/or about 400 cps. The surfactant paste, additional surfactants and non-water viscosity reducing agents may be combined in accordance with other formulas suitable to generate a surfactant paste composition according to the present invention. In an embodiment, the surfactant paste composition may be obtained by adding (A) 30 to 85% by weight of a surfactant paste, (B) 0 to 25% by weight of additional surfactants and (C) 10 to 70% by weight of a non-water viscosity reducing agent, provided that the sum of A, B and C is 100%.

In a further embodiment, the surfactant paste composition comprises less than about 50%, or about 40% water, or less than about 35% water or less than about 30% water by weight. In another embodiment, the surfactant paste composition comprises greater than about 10% by weight of non-water viscosity reducing agents, for example polyethylene glycol, and/or less than about 70% by weight of non-water viscosity reducing agents, for example polyethylene glycol, and/or from about 14% to about 50% by weight of non-water viscosity reducing agents, for example polyethylene glycol, and/or about 20% by weight of non-water viscosity reducing agents, for example polyethylene glycol.

The surfactant paste composition may include additional components including scents, colorants or dyes, disinfectants, soaps, preservatives, antibacterial components, water, skin benefiting agents, rheology modifiers, and surface treating ingredients.

In one non-limiting example, the surfactant paste composition exhibits a pH of from about 3 to about 10 and/or from about 5 to about 9 and/or from about 6 to about 8.

Without wishing to be bound by theory, it is believed that the surfactant paste composition formed by the method disclosed herein will form multiple phases. In one example, the non-water viscosity reducing agent, for example a polyhydroxy compound, forms a continuous phase and the surfactants form a micellar and/or lamellar dispersed phase. The micellar and/or lamellar dispersed phase may contain a small amount of crystalline and/or pseudo crystalline structures as well. The internal dispersed phase provides both an immediate source of surfactants once activated by water or other liquids, along with a reservoir of the surfactants. The reservoir of surfactants is due to the more structured and/or large surfactant particles in the dispersed phase that become available as water dilutes the surfactant paste composition.

Fibrous Structures/Sanitary Tissue Products/Fibrous Structure Articles

The sanitary tissue products of the present invention may be single-ply or multi-ply sanitary tissue products. In other words, the sanitary tissue products of the present invention may comprise one or more fibrous structures. The fibrous structures and/or sanitary tissue products of the present invention are made from a plurality of pulp fibers, for example wood pulp fibers and/or other cellulosic pulp fibers, for example trichomes. In addition to the pulp fibers, the fibrous structures and/or sanitary tissue products of the present invention may comprise synthetic fibers and/or filaments.

Non-limiting examples of the fibrous structures of the present invention may comprise a surface comprising a surface pattern, wherein the surface pattern comprises a continuous knuckle region and a plurality of discrete pillow regions dispersed within the continuous knuckle region, wherein a repeat unit of the surface pattern comprises at least two groups of two or more discrete pillow regions, wherein the at least two groups are non-parallelly juxtaposed, for example the repeat unit is defined by two or more groups of two or more discrete pillow regions, wherein at least two of the two or more groups are non-parallelly juxtaposed.

Non-limiting examples of the fibrous structures of the present invention may comprise a surface comprising a surface pattern, wherein the surface pattern comprises a continuous knuckle region and a plurality of discrete pillow regions dispersed within the continuous knuckle region, wherein a repeat unit of the surface pattern comprises at least two groups of two, for example three, or more discrete pillow regions, wherein at least one of the at least two groups comprises three or more discrete pillow regions and wherein the at least two groups are non-parallelly juxtaposed.

Non-limiting examples of the fibrous structures of the present invention may comprise a surface comprising a surface pattern, wherein the surface pattern comprises a continuous knuckle region and a plurality of discrete pillow regions dispersed within the continuous knuckle region, wherein a repeat unit of the surface pattern comprises at least two groups of two or more discrete pillow regions, wherein the at least one of the two or more groups is oriented at an angle of from about 30° to about 85° and/or from about 45° to about 80° relative to the CD.

Non-limiting examples of the fibrous structures of the present invention may comprise a surface comprising a surface pattern, wherein the surface pattern comprises a continuous knuckle region and a plurality of discrete pillow regions dispersed within the continuous knuckle region, wherein the surface pattern exhibits a concentration of discrete pillow regions within the surface pattern of less than 200 and/or less than 175 and/or less than 150 and/or less than 125 and/or less than 100 and/or less than 75 discrete pillow regions/in^(t) and wherein at least 50% and/or at least 75% and/or at least 85% and/or at least 95% and/or 100% of the discrete pillow regions exhibit a discrete pillow region length to discrete pillow region width of at greater than 3 and/or greater than 3.1 and/or greater than 3.5 and/or greater than 4 and/or greater than 5 and/or greater than 6 and/or greater than 7, and optionally wherein a repeat unit of the surface pattern comprises at least two groups of two or more discrete pillow regions, and optionally wherein the at least two groups are non-parallelly juxtaposed.

Non-limiting examples of the fibrous structures of the present invention comprise a surface comprising a surface pattern, wherein the surface pattern comprises a continuous knuckle region and a plurality of discrete pillow regions dispersed within the continuous knuckle region, wherein a repeat unit of the surface pattern comprises less than 20 discrete pillow regions, and optionally wherein the surface patter comprises at least two groups of two or more discrete pillow regions, and optionally wherein the at least two groups are non-parallelly juxtaposed.

In one example, the fibrous structures of the present invention comprises a surface comprising a surface pattern, wherein the surface pattern comprises a continuous knuckle region and a plurality of discrete pillow regions dispersed within the continuous knuckle region, wherein a repeat unit of the surface pattern is defined by two or more groups of two or more discrete pillow regions, wherein the at least two of the two or more groups are non-parallelly juxtaposed, wherein at least two of the two or more discrete pillow regions within one of the at least two groups are parallel to one another.

In another example, the surface pattern of the fibrous structure may comprise two or more discrete pillow regions within at least two groups that are oriented at an angle of about 90°.

In another example, the surface pattern of the fibrous structure may comprise at least two groups of two or more discrete pillow regions, wherein the at least two groups are oriented at an angle of greater than 20° to less than 85° and/or greater than 30° to less than 85° and/or greater than 35° to less than 80° and/or from about 45° to about 75° to the fibrous structure's cross machine direction.

In another example, the surface pattern of the fibrous structure may comprise at least two discrete pillow regions that are non-parallelly juxtaposed.

In another example, the surface pattern of the fibrous structure may comprise at least two discrete pillow regions within at least two different groups that are non-parallelly juxtaposed.

In one example, the surface pattern of the fibrous structure may comprise at least two of the discrete pillow regions that are the same in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise a plurality of the discrete pillow regions that are the same in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise at least two of the discrete pillow regions within a group that are the same in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise all of the discrete pillow regions within a group that are the same in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise at least two of the discrete pillow regions within at least two groups that are the same in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise all of the discrete pillow regions within at least two groups that are the same in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise at least two of the discrete pillow regions that are different in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise a plurality of the discrete pillow regions that are different in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise at least two of the discrete pillow regions within a group that are different in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise all of the discrete pillow regions within a group that are the different in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise at least two of the discrete pillow regions within at least two groups that are different in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the surface pattern of the fibrous structure may comprise all of the discrete pillow regions within at least two groups that are different in one or more dimensions/properties/characteristics of discrete pillows and/or discrete pillow regions, for example length, width, shape, orientation, etc.

In one example, the fibrous structures of the present invention comprise a plurality of fibers, for example pulp fibers, such as wood pulp fibers and/or non-wood pulp fibers.

In one example, the fibrous structures of the present invention and thus the compacted fibrous structure articles of the present invention may comprise a structured fibrous structure, for example a through-air-dried fibrous structure, such as a creped through-air-dried fibrous structure and/or an uncreped through-air-dried fibrous structure, fabric creped fibrous structure, belt creped fibrous structure, ATMOS fibrous structure, NTT fibrous structure, ETAD fibrous structure, QRT fibrous structure, and STT fibrous structure.

In one example, the compacted fibrous structure article comprises a layered fibrous structure. In one example, the compacted fibrous structure article comprises a non-layered fibrous structure. In one example, the compacted fibrous structure article comprises a non-hydroentangled fibrous structure.

In one example, the fibrous structures of the present invention may comprise a surface pattern that comprises a regular pattern and/or a non-random, repeating pattern and/or a molded microscopical three-dimensional pattern.

Dimensions of discrete pillow regions of the present invention are related to the dimensions of the discrete pillows within the molding members since the discrete pillows impart the discrete pillow regions to the fibrous structures of the present invention.

In one example, the fibrous structures of the present invention may comprise a surface pattern that is wet-formed, for example during the papermaking process for making the fibrous structure.

The fibrous structures of the present invention may be employed as a fibrous structure ply or fibrous structure plies in single- and/or multi-ply sanitary tissue products, for example single- or multi-ply sanitary tissue products with one or more other fibrous structure plies.

The fibrous structures and/or sanitary tissue products of the present invention may exhibit an average TS7 value of less than 10 and/or less than 9 and/or less than 8 and/or less than 7 and/or less than 6 and/or less than 5.5 and/or greater than 4 and/or greater than 4.5 and/or greater than 5 dB V² rms as measured according to the Emtec Test Method described herein.

The fibrous structures and/or sanitary tissue products of the present invention may be creped or uncreped.

The fibrous structures and/or sanitary tissue products of the present invention may be wet-laid or air-laid.

The fibrous structures and/or sanitary tissue products of the present invention may be embossed.

The fibrous structures and/or sanitary tissue products of the present invention may comprise a surface softening agent or be void of a surface softening agent. In one example, the sanitary tissue product is a non-lotioned sanitary tissue product, such as a sanitary tissue product comprising a non-lotioned fibrous structure ply, for example a non-lotioned through-air-dried fibrous structure ply, for example a non-lotioned creped through-air-dried fibrous structure ply and/or a non-lotioned uncreped through-air-dried fibrous structure ply. In yet another example, the sanitary tissue product may comprise a non-lotioned fabric creped fibrous structure ply and/or a non-lotioned belt creped fibrous structure ply.

The fibrous structures and/or sanitary tissue products of the present invention may comprise trichome fibers and/or may be void of trichome fibers.

In one example, the fibrous structure of the present invention, for example a paper towel, may comprise a series of line embossments 32 and dot embossments 34 in combination with a knuckle and pillow molded microscopical three-dimensional pattern.

In one example, the fibrous structures and/or sanitary tissue products of the present invention may exhibit one or more of the following properties:

A basis weight of between about 30 g/m² and about 80 g/m², or between about 40 g/m² and about 65 g/m², or between about 45 g/m² and about 60 g/m², or between about 50 g/m² and about 58 g/m², or between about 50 g/m² and about 55 g/m² as measured according to the Basis Weight Test Method described herein.

An Emtec TS7 value of less than about 20.00 dB V² rms, or less than about 19.50 dB V² rms, or less than about 19.00 dB V² rms, or less than about 18.50 dB V² rms, or less than about 18.00 dB V²rms, or less than about 17.50 dB V² rms, or between about 0.01 dB V²rms and about 20.00 dB V²rms, or between about 0.01 dB V²rms and about 19.50 dB V² rms, or between about 0.01 dB V²rms and about 19.00 dB V²rms, or between about 0.01 dB V²rms and about 18.50 dB V² rms, or between about 0.01 dB V² rms and about 18.00 dB V² rms, or between about 0.01 dB V²rms and about 17.50 dB V²rms, or between about 5.0 dB V²rms and about 20.00 dB V²rms, or between about 10.00 dB V² rms and about 20.00 dB V² rms, or between about 15.00 dB V² rms and about 20.00 dB V² rms as measured according to the Emtec Test Method described herein.

An SST value (absorbency rate) of greater than about 1.60 g/sec^(0.5), or greater than about 1.65 g/sec^(0.5), or greater than about 1.70 g/sec^(0.5), or greater than about 1.75 g/sec^(0.5), or greater than about 1.80 g/sec^(0.5), or greater than about 1.82 g/sec^(0.5), or greater than about 1.85 g/sec^(0.5), or greater than about 1.88 g/sec^(0.5), or greater than about1.90 g/sec^(0.5), or greater than about 1.95 g/sec^(0.5), or greater than about 2.00 g/sec^(0.5), or between about 1.60 g/sec^(0.5) and about 2.50 g/sec^(0.5), or between about 1.65 g/sec^(0.5) and about 2.50 g/sec^(0.5), or between about 1.70 g/sec^(0.5) and about 2.40 g/sec^(0.5), or between about 1.75 g/sec^(0.5) and about 2.30 g/sec^(0.5), or between about 1.80 g/sec^(0.5) and about 2.20 g/sec^(0.5), or between about 1.82 g/sec^(0.5) and about 2.10 g/sec^(0.5), or between about 1.85 g/sec^(0.5) and about 2.00 g/sec^(0.5) as measured according to the SST Absorbency Rate Test Method described herein.

A Plate Stiffness value of greater than about 12 N*mm, or greater than about 12.5 N*mm, or greater than about 13.0 N*mm, or greater than about 13.5 N*mm, or greater than about 14 N*mm, or greater than about 14.5 N*mm, or greater than about 15 N*mm, or greater than about 15.5 N*mm, or greater than about 16 N*mm, or greater than about 16.5 N*mm, or greater than about 17 N*mm, or between about 12 N*mm and about 20 N*mm, or between about 12.5 N*mm and about 20 N*mm, or between about 13 N*mm and about 20 N*mm, or between about 13.5 N*mm and about 20 N*mm, or between about 14 N*mm between about 20 N*mm, or between about 14.5 N*mm and about 20 N*mm, or between about 15 N*mm and about 20 N*mm, or between about 15.5 N*mm and about 20 N*mm, or between about 16 N*mm and about 20 N*mm, or between about 16.5 N*mm and about 20 N*mm, or between about 17 N*mm and about 20 N*mm as measured according to the Plate Stiffness Test Method described herein. To convert N*mm to g*mm multiply N value by 101.97 to obtain the g*mm value.

A Resilient Bulk value of greater than about 85 cm³/g, or greater than about 90 cm³/g, or greater than about 95 cm³/g, or greater than about 100 cm³/g, or greater than about 102 cm³/g, or greater than about 105 cm³/g, or between about 85 cm³/g and about 110 cm³/g, or between about 90 cm³/g and about 110 cm³/g, or between about 95 cm³/g and about 110 cm³/g, or between about 100 cm³/g and about 110 cm³/g as measured according to the Stack Compressibility and Resilient Bulk Test Method described herein.

A Total Wet Tensile value of greater than about 400 g/in, or greater than about 450 g/in, or greater than about 500 g/in, or greater than about 550 g/in, or greater than about 600 g/in, or greater than about 650 g/in, or greater than about 700 g/in, or greater than about 750 g/in, or greater than about 800 g/in, or greater than about 850 g/in, or greater than about 900 g/in, or between about 400 g/in and about 900 g/in, or between about 450 g/in and about 900 g/in, or between about 500 g/in and about 900 g/in, or between about 550 g/in and about 900 g/in, or between about 600 g/in and about 900 g/in, or between about 650 g/in and about 900 g/in, or between about 700 g/in and about 900 g/in as measured according to the Wet Tensile Test Method described herein.

A Wet Burst value of greater than about 300 g, or greater than about 350 g, or greater than about 400 g, or greater than about 450 g, or greater than about 500 g, or greater than about 550 g, or greater than about 600 g, or between about 300 g and about 650 g, or between about 350 g and about 600 g, or between about 350 g and about 550 g, or between about 400 g and about 550 g, or between about 400 g and about 525 g as measured according to the Wet Burst Test Method described herein.

A Flexural Rigidity value of greater than about 700 mg-cm, or greater than about 800 mg-cm, or greater than about 900 mg-cm, or greater than about 1000 mg-cm, or greater than about 1100 mg-cm, or greater than about 1200 mg-cm, or greater than about 1300 mg-cm, or greater than about 1400 mg-cm, or greater than about 1500 mg-cm, or greater than about 1600 mg-cm, or greater than about 1700 mg-cm, or between about 700 mg-cm and about 1700 mg-cm, or between about 800 mg-cm and about 1500 mg-cm, or between about 900 mg-cm and about 1400 mg-cm, or between about 1000 mg-cm and about 1350 mg-cm, or between about 1050 mg-cm and about 1350 mg-cm, or between about 1100 mg-cm and about 1350 mg-cm, or between about 1100 mg-cm and about 1300 mg-cm as measured according to the Flexural Rigidity Test Method described herein.

A Dry Caliper value of greater than about 26.0 mils, or greater than about 40 mils, or between about 26.0 mils and about 80.0 mils, or between 40.0 mils and 60.0 mils, specifically reciting all 0.10 mil increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the Caliper Test Method described herein.

A Wet Caliper value of greater than about 17.0 mils, or greater than about 26 mils, or between about 26.0 mils and about 70.0 mils, or between about 26.0 mils and about 40.0 mils, specifically reciting all 0.10 mil increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the Caliper Test Method described herein.

A Total Dry Tensile (Total Tensile) value of greater than about 1300 g/in, or greater than about 1700 g/in, or between about 1300 g/in and about 8000 g/in, or between about 1800 g/in and about 7000 g/in or between about 2000 g/in and about 6000 g/in or between about 2000 g/in and 5000 g/in, specifically reciting all 10 g/in increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the Dry Tensile Strength Test Method described herein.

A Geometric Mean Dry Modulus value of greater than about 1000 g/cm, or greater than about 1700 g/cm, or between about 1800 g/cm and about 4000 g/cm, or between about 1800 g/cm and about 3500 g/cm, specifically reciting all 10 g/cm increments within the above-recited ranges and all ranges formed therein or thereby as measure according to the Dry Modulus Test Method described herein.

A Wet Tensile Geometric Mean Modulus value of greater than about 250 g/cm, or greater than about 375 g/cm, or between about 250 g/cm and about 700 g/cm, or between about 250 g/cm and about 525 g/cm, or between about 375 g/cm and 525 g/cm, specifically reciting all 10 g/cm increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the Wet Tensile Test Method described herein.

A CRT rate value of greater than about 0.30 g/sec, or greater than about 0.61 g/sec, or between about 0.30 g/sec and about 1.00 g/sec, or between about 0.61 g/sec and about 0.85 g/sec, specifically reciting all 0.05 g/sec increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the SST Absorbency Rate Test Method described herein.

A CRT capacity value of greater than about 10.0 g/g, or greater than about 12.5 g/g, or between about 12.5 g/g and about 23.0 g/g, or between about 16.5 g/g and about 21.5 g/g, specifically reciting all 0.1 g/g increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the SST Absorbency Rate Test Method described herein.

An Emtec TS750 value of greater than about 40 dB V² rms, or greater than about 50 dB V² rms, or between about 50 dB V² rms and about 100 dB V² rms, specifically reciting all 10 dB V² rms increments within the above-recited ranges and all ranges formed therein or thereby as measured according to the Emtec Test Method described herein.

A Slip Stick Coefficient of Friction (“Slip Stick COF”) value of greater than about 700, or between about 700 and about 1150, or between about 725 and about 1130 (COF*10000), specifically reciting all increments of 10 within the above-recited ranges and all ranges formed therein or thereby as measured according to the Slip Stick Coefficient of Friction Test Method.

A Kinetic Coefficient of Friction value of greater than about 0.85, or between about 0.85 and about 1.30, or between about 0.85 and about 1.20, specifically reciting all 0.05 increments within the above-recited ranges and all ranges formed therein or thereby.

In one example, the fibrous structures and/or sanitary tissue products of the present invention may comprise a single-ply and exhibit a total dry tensile of at least 3000 g/in and/or at least 4000 g/in and/or at least 4500 g/in and/or at least 5000 g/in and/or at least 5500 g/in and/or at least 6000 g/in as measured according to the Dry Tensile Test Method described herein and comprise a surface pattern formed from the molding member shown in FIG. 8A or 8B.

Molding Members

The fibrous structures of the present invention can be made using a molding member, for example a papermaking belt, with knuckles and pillows in a molded three-dimensional pattern. The papermaking belt can be thought of as a molding member. A “molding member” is a structural element having cell sizes and placement as described herein that can be used as a support for an embryonic web comprising a plurality of cellulosic fibers and/or a plurality of synthetic fibers as well as to “mold” a desired geometry of the fibrous structures during papermaking (excluding “dry” processes such as embossing). The molding member can comprise fluid-permeable areas and can impart a three-dimensional pattern of knuckles to the fibrous structure being produced thereon, and includes, without limitation, single-layer and multi-layer structures in the class of papermaking belts having UV-cured resin knuckles on a woven reinforcing member as disclosed in the above-mentioned U.S. Pat. No. 6,610,173, issued to Lindsay et al. or U.S. Pat. No. 4,514,345 issued to Trokhan.

In one example, the papermaking belt is a fabric crepe belt for use in a process as disclosed in the above-mentioned U.S. Pat. No. 7,494,563, issued to Edwards, but having a pattern of cells, i.e., knuckles, as disclosed herein. Fabric crepe belts can be made by extruding, coating, or otherwise applying a polymer, resin, or other curable material onto a support member, such that the resulting pattern of three-dimensional features are belt knuckles with the pillow regions serving as large, recessed pockets. In another example, the papermaking belt can be a continuous knuckle belt of the type exemplified in FIG. 1 of U.S. Pat. No. 4,514,345 issued to Trokhan, having deflection conduits that serve as the recessed pockets of the belt shown and described in U.S. Pat. No. 7,494,563, for example in place of the fabric crepe belt shown and described therein.

The fibrous structures and/or sanitary tissue products of the present invention and/or fibrous structure plies employed in the sanitary tissue products of the present invention are formed on molding members, for example patterned molding members, that result in the fibrous structures and/or sanitary tissue products of the present invention. In one example, the molding member comprises a non-random repeating pattern. In another example, the molding member comprises a resinous pattern.

A “reinforcing element” may be a desirable (but not necessary) element in some examples of the molding member, serving primarily to provide or facilitate integrity, stability, and durability of the molding member comprising, for example, a resinous material. The reinforcing element can be fluid-permeable or partially fluid-permeable, may have a variety of embodiments and weave patterns, and may comprise a variety of materials, such as, for example, a plurality of interwoven yarns (including Jacquard-type and the like woven patterns), a felt, a plastic, other suitable synthetic material, or any combination thereof.

As described herein, a non-limiting example of a molding member suitable for use in the present invention may comprise a through-air-drying belt comprising resin on a surface of and/or locked onto (for example a portion of the resin penetrates through) a reinforcing element in a pattern.

Without wishing to be bound by theory, foreshortening (dry & wet crepe, fabric crepe, rush transfer, etc) is an integral part of fibrous structure and/or sanitary tissue paper making, helping to produce the desired balance of strength, stretch, softness, absorbency, etc. Fibrous structure support, transport and molding members used in the papermaking process, such as rolls, wires, felts, fabrics, belts, etc. have been variously engineered to interact with foreshortening to further control the fibrous structure and/or sanitary tissue product properties.

In an example of a method for making fibrous structures of the present invention, the method can comprise the steps of:

-   -   (a) providing a fibrous furnish comprising fibers; and     -   (b) depositing the fibrous furnish onto a molding member such         that at least one fiber is deflected out-of-plane of the other         fibers present on the molding member.

In another example of a method for making a fibrous structure of the present invention, the method comprises the steps of:

-   -   (a) providing a fibrous furnish comprising fibers;     -   (b) depositing the fibrous furnish onto a foraminous member to         form an embryonic fibrous web;     -   (c) associating the embryonic fibrous web with a papermaking         belt having a pattern of knuckles as disclosed herein such that         at a portion of the fibers are deflected out-of-plane of the         other fibers present in the embryonic fibrous web; and     -   (d) drying said embryonic fibrous web such that that the dried         fibrous structure is formed.

In another example of a method for making the fibrous structures of the present invention, the method can comprise the steps of:

(a) providing a fibrous furnish comprising fibers;

(b) depositing the fibrous furnish onto a foraminous member such that an embryonic fibrous web is formed;

(c) associating the embryonic web with a papermaking belt having a pattern of knuckles as disclosed herein such that at a portion of the fibers can be formed in the substantially continuous deflection conduits;

(d) deflecting a portion of the fibers in the embryonic fibrous web into the substantially continuous deflection conduits and removing water from the embryonic web so as to form an intermediate fibrous web under such conditions that the deflection of fibers is initiated no later than the time at which the water removal through the discrete deflection cells or the substantially continuous deflection conduits is initiated; and

(e) optionally, drying the intermediate fibrous web; and

(f) optionally, foreshortening the intermediate fibrous web, such as by creping.

A non-limiting example of a process and equipment for making fibrous structures according to the present invention comprises supplying an aqueous dispersion of fibers (a fibrous furnish) to a headbox which can be of any design known to those of skill in the art. The aqueous dispersion of fibers can include wood and non-wood fibers, northern softwood kraft fibers (“NSK”), eucalyptus fibers, SSK, NHK, acacia, bamboo, straw and bast fibers (wheat, flax, rice, barley, etc.), corn stalks, bagasse, reed, synthetic fibers (PP, PET, PE, bico version of such fibers), regenerated cellulose fibers (viscose, lyocell, etc.), and other fibers known in the papermaking art. From the headbox, the aqueous dispersion of fibers can be delivered to a foraminous member, which can be a Fourdrinier wire, to produce an embryonic fibrous web.

The foraminous member can be supported by a breast roll and a plurality of return rolls of which only two are illustrated. The foraminous member can be propelled in the direction indicated by directional arrow by a drive means, at a predetermined velocity, V₁. Optional auxiliary units and/or devices commonly associated with fibrous structure making machines and with the foraminous member comprise forming boards, hydrofoils, vacuum boxes, tension rolls, support rolls, wire cleaning showers, and other various components known to those of skill in the art.

After the aqueous dispersion of fibers is deposited onto the foraminous member, the embryonic fibrous web is formed, typically by the removal of a portion of the aqueous dispersing medium by techniques known to those skilled in the art. Vacuum boxes, forming boards, hydrofoils, and other various equipment known to those of skill in the art are useful in effectuating water removal. The embryonic fibrous web can travel with the foraminous member about return roll and can be brought into contact with a papermaking belt in a transfer zone, after which the embryonic fibrous web travels on the papermaking belt. While in contact with the papermaking belt, the embryonic fibrous web can be deflected, rearranged, and/or further dewatered. Depending on the process, mechanical and fluid pressure differential, alone or in combination, can be utilized to deflect a portion of fibers into the deflection conduits of the papermaking belt. For example, in a through-air drying process a vacuum apparatus can apply a fluid pressure differential to the embryonic web disposed on the papermaking belt, thereby deflecting fibers into the deflection conduits of the deflection member. The process of deflection may be continued with additional vacuum pressure, if necessary, to even further deflect and dewater the fibers of the web into the deflection conduits of the papermaking belt.

The papermaking belt can be in the form of an endless belt. In this simplified representation, the papermaking belt passes around and about papermaking belt return rolls and impression nip roll and can travel in the direction indicated by directional arrow, at a papermaking belt velocity V₂, which can be less than, equal to, or greater than, the foraminous member velocity V₁. In the present invention, the papermaking belt velocity V₂ is less than foraminous member velocity V₁ such that the partially-dried fibrous web is foreshortened in the transfer zone by a percentage determined by the relative velocity differential between the foraminous member and the papermaking belt. Associated with the papermaking belt can be various support rolls, other return rolls, cleaning means, drive means, and other various equipment known to those of skill in the art that may be commonly used in fibrous structure making machines.

The papermaking belts of the present invention can be made, or partially made, according to the process described in U.S. Pat. No. 4,637,859, issued Jan. 20, 1987, to Trokhan, and having the patterns of cells as disclosed herein.

The fibrous web can then be creped with a creping blade to remove the web from the surface of the Yankee dryer resulting in the production of a creped fibrous structure in accordance with the present invention. As used herein, creping refers to the reduction in length of a dry (having a consistency of at least about 90% and/or at least about 95%) fibrous web which occurs when energy is applied to the dry fibrous web in such a way that the length of the fibrous web is reduced and the fibers in the fibrous web are rearranged with an accompanying disruption of fiber-fiber bonds. Creping can be accomplished in any of several ways as is well known in the art, as the doctor blades can be set at various angles. The creped fibrous structure is wound on a reel, commonly referred to as a parent roll, and can be subjected to post processing steps such as calendaring, tuft generating operations, embossing, and/or converting. The reel winds the creped fibrous structure at a reel surface velocity, V₄.

The papermaking belts of the present invention can be utilized to form discrete elements and a continuous/substantially continuous network (i.e., knuckles and pillows) into a fibrous structure during a through-air-drying operation. The discrete elements can be knuckles and can be relatively high density relative to the continuous/substantially continuous network, which can be a continuous/substantially pillow having a relatively lower density. In other examples, the discrete elements can be pillows and can be relatively low density relative to the continuous/substantially continuous network, which can be a continuous/substantially continuous knuckle having a relatively higher density. In the example detailed above, the fibrous structure is a homogenous fibrous structure, but such papermaking process may also be adapted to manufacture layered fibrous structures, as is known in the art.

As discussed above, the fibrous structure can be embossed during a converting operating to produce the embossed fibrous structures of the present invention.

In one example of the present invention, the compacted fibrous structure article comprises a fibrous structure article comprising a fibrous structure formed on a molding member 114 as shown in FIG. 8A and alternatively FIG. 8B comprising a continuous pillow network deflection conduit (represented by white lines throughout the pattern in FIGS. 8A and 8B), which imparts a continuous pillow network in a fibrous structure made on such molding members, wherein the continuous pillow network deflection conduit contains within it dispersed discrete zones/regions of a continuous knuckle network resin (represented by black lines within the pattern in FIGS. 8A and 8B), which imparts discrete continuous knuckle networks (78 in FIG. 8C) within the continuous pillow network in a fibrous structure made on such molding members, wherein the discrete continuous network resin in turn contains within it dispersed discrete pillow deflection conduits (represented by white polygons within the pattern in FIGS. 8A and 8B), which imparts discrete pillows (80 in FIG. 8C) in a fibrous structure made on such molding members, wherein the discrete pillows are dispersed throughout the discrete continuous knuckle network as shown in FIG. 8C. Examples of fibrous structure made on such belts are shown images of FIG. 8C which shows two different magnifications and one fibrous structure containing viscose fibers (in this case Danufil® fibers from Kelheim Fibres GmbH, Kelheim, Germany) and one fibrous structure that does not.

Non-Limiting Examples of Making Fibrous Structures and/or Sanitary Tissue Products

In one example, the method for making the fibrous structures and/or sanitary tissue products of the present invention may be a fibrous structure and/or sanitary tissue product making process that uses a cylindrical dryer such as a Yankee (a Yankee-process) or it may be a Yankeeless process as is used to make substantially uniform density and/or uncreped fibrous structures and/or sanitary tissue products. Alternatively, the fibrous structures and/or sanitary tissue products may be made by an air-laid process and/or meltblown and/or spunbond processes and any combinations thereof so long as the fibrous structures and/or sanitary tissue products of the present invention are made thereby.

As shown in FIG. 9, one example of a process and equipment, represented as 100 for making a sanitary tissue product according to the present invention comprises supplying an aqueous dispersion of fibers (a fibrous furnish or fiber slurry) to a headbox 102 which can be of any convenient design. From headbox 102 the aqueous dispersion of fibers is delivered to a first foraminous member 104 which is typically a Fourdrinier wire, to produce an embryonic fibrous structure 106.

The first foraminous member 104 may be supported by a breast roll 108 and a plurality of return rolls 110 of which only two are shown. The first foraminous member 104 can be propelled in the direction indicated by directional arrow 112 by a drive means, not shown. Optional auxiliary units and/or devices commonly associated fibrous structure making machines and with the first foraminous member 104, but not shown, include forming boards, hydrofoils, vacuum boxes, tension rolls, support rolls, wire cleaning showers, and the like.

After the aqueous dispersion of fibers is deposited onto the first foraminous member 104, embryonic fibrous structure 106 is formed, typically by the removal of a portion of the aqueous dispersing medium by techniques well known to those skilled in the art. Vacuum boxes, forming boards, hydrofoils, and the like are useful in effecting water removal. The embryonic fibrous structure 106 may travel with the first foraminous member 104 about return roll 110 and is brought into contact with a patterned molding member 114, such as a 3D patterned through-air-drying belt. While in contact with the patterned molding member 114, the embryonic fibrous structure 106 will be deflected, rearranged, and/or further dewatered.

The patterned molding member 114 may be in the form of an endless belt. In this simplified representation, the patterned molding member 114 passes around and about patterned molding member return rolls 116 and impression nip roll 118 and may travel in the direction indicated by directional arrow 120. Associated with patterned molding member 114, but not shown, may be various support rolls, other return rolls, cleaning means, drive means well known to those skilled in the art that may be commonly used in fibrous structure making machines.

After the embryonic fibrous structure 106 has been associated with the patterned molding member 114, fibers within the embryonic fibrous structure 106 are deflected into pillows and/or pillow network (“deflection conduits”) present in the patterned molding member 114. In one example of this process step, there is essentially no water removal from the embryonic fibrous structure 106 through the deflection conduits after the embryonic fibrous structure 106 has been associated with the patterned molding member 114 but prior to the deflecting of the fibers into the deflection conduits. Further water removal from the embryonic fibrous structure 106 can occur during and/or after the time the fibers are being deflected into the deflection conduits. Water removal from the embryonic fibrous structure 106 may continue until the consistency of the embryonic fibrous structure 106 associated with patterned molding member 114 is increased to from about 25% to about 35%. Once this consistency of the embryonic fibrous structure 106 is achieved, then the embryonic fibrous structure 106 can be referred to as an intermediate fibrous structure 122. During the process of forming the embryonic fibrous structure 106, sufficient water may be removed, such as by a noncompressive process, from the embryonic fibrous structure 106 before it becomes associated with the patterned molding member 114 so that the consistency of the embryonic fibrous structure 116 may be from about 10% to about 30%.

While applicants decline to be bound by any particular theory of operation, it appears that the deflection of the fibers in the embryonic fibrous structure and water removal from the embryonic fibrous structure begin essentially simultaneously. Embodiments can, however, be envisioned wherein deflection and water removal are sequential operations. Under the influence of the applied differential fluid pressure, for example, the fibers may be deflected into the deflection conduit with an attendant rearrangement of the fibers. Water removal may occur with a continued rearrangement of fibers. Deflection of the fibers, and of the embryonic fibrous structure, may cause an apparent increase in surface area of the embryonic fibrous structure. Further, the rearrangement of fibers may appear to cause a rearrangement in the spaces or capillaries existing between and/or among fibers.

It is believed that the rearrangement of the fibers can take one of two modes dependent on a number of factors such as, for example, fiber length. The free ends of longer fibers can be merely bent in the space defined by the deflection conduit while the opposite ends are restrained in the region of the ridges. Shorter fibers, on the other hand, can actually be transported from the region of the ridges into the deflection conduit (The fibers in the deflection conduits will also be rearranged relative to one another). Naturally, it is possible for both modes of rearrangement to occur simultaneously.

As noted, water removal occurs both during and after deflection; this water removal may result in a decrease in fiber mobility in the embryonic fibrous structure. This decrease in fiber mobility may tend to fix and/or freeze the fibers in place after they have been deflected and rearranged. Of course, the drying of the fibrous structure in a later step in the process of this invention serves to more firmly fix and/or freeze the fibers in position.

Any convenient means conventionally known in the papermaking art can be used to dry the intermediate fibrous structure 122. Examples of such suitable drying process include subjecting the intermediate fibrous structure 122 to conventional and/or flow-through dryers and/or Yankee dryers.

In one example of a drying process, the intermediate fibrous structure 122 in association with the patterned molding member 114 passes around the patterned molding member return roll 116 and travels in the direction indicated by directional arrow 120. The intermediate fibrous structure 122 may first pass through an optional predryer 124. This predryer 124 can be a conventional flow-through dryer (hot air dryer) well known to those skilled in the art. Optionally, the predryer 124 can be a so-called capillary dewatering apparatus. In such an apparatus, the intermediate fibrous structure 122 passes over a sector of a cylinder having preferential-capillary-size pores through its cylindrical-shaped porous cover. Optionally, the predryer 124 can be a combination capillary dewatering apparatus and flow-through dryer. The quantity of water removed in the predryer 124 may be controlled so that a predried fibrous structure 126 exiting the predryer 124 has a consistency of from about 30% to about 98%. The predried fibrous structure 126, which may still be associated with patterned molding member 114, may pass around another patterned molding member return roll 116 and as it travels to an impression nip roll 118. As the predried fibrous structure 126 passes through the nip formed between impression nip roll 118 and a surface of a Yankee dryer 128, the pattern formed by the top surface 130 of patterned molding member 114 is impressed into the predried fibrous structure 126 to form a 3D patterned fibrous structure 132. The imprinted fibrous structure 132 can then be adhered to the surface of the Yankee dryer 128 where it can be dried to a consistency of at least about 95%.

The 3D patterned fibrous structure 132 can then be foreshortened by creping the 3D patterned fibrous structure 132 with a creping blade 133 to remove the 3D patterned fibrous structure 132 from the surface of the Yankee dryer 128 resulting in the production of a 3D patterned creped fibrous structure 134 in accordance with the present invention, wherein the 3D patterned creped fibrous structure has a fabric-side-out (FSO) surface that has pillows imparted to it by the patterned molding member 114 protruding outward and a wire-side-out (WSO) surface that did not contact the patterned molding member 114 during the making process, but rather contacted the first foraminous member 104, in this case the Fourdrinier wire. As used herein, foreshortening refers to the reduction in length of a dry (having a consistency of at least about 90% and/or at least about 95%) fibrous structure which occurs when energy is applied to the dry fibrous structure in such a way that the length of the fibrous structure is reduced and the fibers in the fibrous structure are rearranged with an accompanying disruption of fiber-fiber bonds. Foreshortening can be accomplished in any of several well-known ways. One common method of foreshortening is creping. The 3D patterned creped fibrous structure 134 may be subjected to post processing steps such as calendaring, tuft generating operations, and/or embossing and/or converting.

Another example of making fibrous structures, for example paper towels, in accordance with the present invention using the papermaking machine described in FIG. 8 is described below.

A 3% by weight aqueous slurry of northern softwood kraft (NSK) pulp is made up in a conventional re-pulper. The NSK slurry is refined gently and a 2% solution of a permanent wet strength resin (i.e. Kymene 5221 marketed by Solenis incorporated of Wilmington, Del.) is added to the NSK stock pipe at a rate of 1% by weight of the dry fibers. Kymene 5221 is added as a wet strength additive. The adsorption of Kymene 5221 to NSK is enhanced by an in-line mixer. A 1% solution of Carboxy Methyl Cellulose (CMC) (i.e. FinnFix 700 marketed by C.P. Kelco U.S. Inc. of Atlanta, Ga.) is added after the in-line mixer at a rate of 0.2% by weight of the dry fibers to enhance the dry strength of the fibrous substrate. A 3% by weight aqueous slurry of hardwood Eucalyptus fibers is made up in a conventional re-pulper. A 1% solution of defoamer (i.e. BuBreak 4330 marketed by Buckman Labs, Memphis TS) is added to the Eucalyptus stock pipe at a rate of 0.25% by weight of the dry fibers and its adsorption is enhanced by an in-line mixer.

The NSK furnish and the Eucalyptus fibers are combined in the head box and deposited onto a Fourdrinier wire, running at a first velocity V₁, homogenously to form an embryonic web. The web is then transferred at the transfer zone from the Fourdrinier forming wire at a fiber consistency of about 15% to the papermaking belt, the papermaking belt moving at a second velocity, V₂. The papermaking belt has a pattern of raised portions (i.e., knuckles) extending from a reinforcing member, the raised portions defining either a plurality of discrete or a continuous/substantially continuous deflection conduit portion. The transfer occurs in the transfer zone without precipitating substantial densification of the web. The web is then forwarded, at the second velocity, V₂, on the papermaking belt along a looped path in contacting relation with a transfer head disposed at the transfer zone, the second velocity being from about 1% to about 40% slower than the first velocity, V₁. Since the Fourdrinier wire speed is faster than the papermaking belt, wet shortening, i.e., foreshortening, of the web occurs at the transfer point. In an example, the second velocity V₂ can be from about 0% to about 5% faster than the first velocity V₁.

Further de-watering is accomplished by vacuum assisted drainage until the web has a fiber consistency of about 15% to about 30%. The patterned web is pre-dried by air blow-through, i.e., through-air-drying (TAD), to a fiber consistency of about 65% by weight. The web is then adhered to the surface of a Yankee dryer with a sprayed creping adhesive comprising 0.25% aqueous solution of polyvinyl alcohol (PVA). The fiber consistency is increased to an estimated 95%-97% before dry creping the web with a doctor blade. The doctor blade has a bevel angle of about 45 degrees and is positioned with respect to the Yankee dryer to provide an impact angle of about 101 degrees. This doctor blade position permits the adequate amount of force to be applied to the substrate to remove it off the Yankee while minimally disturbing the previously generated web structure. The dried web is reeled onto a take up roll (known as a parent roll), the surface of the take up roll moving at a fourth velocity, V₄, that is faster than the third velocity, V₃, of the Yankee dryer. By reeling at a fourth velocity, V₄, that is about 1% to 20% faster than the third velocity, V₃, some of the foreshortening provided by the creping step is “pulled out,” sometimes referred to as a “positive draw,” so that the paper can be more stable for any further converting operations. In other examples, a “negative draw” as is known in the art is also contemplated.

Two plies of the web can be formed into paper towel products by embossing and laminating them together using PVA adhesive. The paper towel has about 53 g/m² basis weight and contains 65% by weight Northern Softwood Kraft and 35% by weight Eucalyptus furnish. The sanitary tissue product is soft, flexible and absorbent.

NON-LIMITING EXAMPLES OF MAKING COMPACTED FIBROUS STRUCTURE ARTICLES Example 1 A Dry-to-the-Touch Compacted Paper Towel Comprising a Surfactant Paste Composition

Examples of dry fibrous structures; namely, paper towels, are produced utilizing a cellulosic pulp fiber furnish consisting of about 48% Northern Bleached Softwood Kraft (“NSK”) (Resolute), about 20% viscose fibers (Danufil®—Kelheim-fibres), about 20% Eucalyptus Bleached Kraft (“Euc”) (Fibria), and about 12% simulated broke. Any furnish preparation and refining methodology common to the papermaking industry can be utilized.

A 3% active solution Kymene 5221 is added to the NSK prior to an in-line static mixer to make an NSK fiber stream and 1% active solution of Wickit 1285, an ethoxylated fatty alcohol available from Ashland Inc., is added to the Euc to make a Euc fiber stream. The addition levels of the respective active solutions are 21 and 1 lbs active/ton of paper towel (fibrous structure), respectively. The NSK fiber stream, Euc fiber stream, viscose fiber stream, and simulated broke fiber stream are separate streams until combining in the headbox.

A 1% active carboxymethylcellulose (CMC—Finnfix) solution at a total level of 7 lbs active/ton of paper towel is added to the NSK fiber stream and/or Euc fiber stream.

The NSK fiber stream, Euc fiber stream, viscose fiber stream, and simulated broke fiber stream are then combined and then diluted with white water at the inlet of a fan pump to a consistency of about 0.15% based on total weight of NSK fibers, Euc fibers, viscose fibers and simulated broke fiber. The diluted fiber slurry is then directed to a non-layered configuration headbox such that an embryonic wet web is formed onto a Fourdrinier wire (foraminous wire) to form a non-layered fibrous structure. Optionally, a fines retention/drainage aid may be added to the outlet of the fan pump.

Dewatering occurs through the Fourdrinier wire and is assisted by deflector and vacuum boxes. The Fourdrinier wire is of a 5-shed, satin weave configuration having 87 machine-direction and 76 cross-direction monofilaments per inch, respectively. The speed of the Fourdrinier wire is about 750 fpm (feet per minute).

The embryonic wet web is transferred from the Fourdrinier wire at a fiber consistency of about 24% at the point of transfer, to a patterned belt, such as a patterned belt through-air-drying resin carrying fabric, for example a molding member, such as the molding member as shown in FIG. 8A. In the present case, the speed of the patterned belt is traveling slower, for example about 20% slower than the speed of the Fourdrinier wire (for example a wet molding process).

Further de-watering is accomplished by vacuum assisted drainage until the web (fibrous structure) has a fiber consistency of about 30%.

While remaining in contact with the patterned belt, the web is pre-dried by air blow-through pre-dryers to a fiber consistency of about 65% by weight.

After the pre-dryers, the semi-dry web is transferred to a Yankee dryer and adhered to the surface of the Yankee dryer with a sprayed creping adhesive. The creping adhesive is an aqueous dispersion with the actives consisting of about 75% polyvinyl alcohol, and about 25% CREPETROL® R6390. Optionally a crepe aid consisting of CREPETROL® A3025 may be applied. CREPETROL® R6390 and CREPETROL® A3025 are commercially available from Ashland Inc. (formerly Hercules Inc.). The creping adhesive diluted to about 0.15% adhesive solids and delivered to the Yankee surface at a rate of about 2# adhesive solids based on the dry weight of the web. The fiber consistency is increased to about 97% before the web is dry creped from the Yankee with a doctor blade.

In the present case, the doctor blade has a bevel angle of about 45° and is positioned with respect to the Yankee dryer to provide an impact angle of about 101° and the reel is run at a speed that is about 15% faster than the speed of the Yankee. In another case, the doctor blade may have a bevel angle of about 25° and be positioned with respect to the Yankee dryer to provide an impact angle of about 81° and the reel is run at a speed that is about 10% slower than the speed of the Yankee. The Yankee dryer is operated at a temperature of about 177° C. and a speed of about 800 fpm. The fibrous structure is wound in a roll using a surface driven reel drum having a surface speed of about 656 feet per minute. The fibrous structure is made at a basis weight of from about 70 gsm to about 90 gsm, for example about 81 gsm. The creped fibrous structure after removal from the Yankee dryer exhibits both a fabric-side-out (FSO) surface (the surface not contacting the Yankee dryer in this case), and a wire-side-out (WSO) surface (the surface contacting the Yankee dryer in this case).

The fibrous structure exhibits the following properties: 1) FSO Moist Contact Area of 14.5% and FSO Moist Depth of less than −375 μm and/or less than −400 μm; namely −418 μm (Inventive Point 1 on Moist Contact Area (%) to Moist Depth (μm) graph in FIG. 10) and WSO Moist Contact Area of 21.8% and WSO Moist Depth of less than −375 μm and/or less than −400 μm; namely −401 μm (Inventive Point 2 on Moist Contact Area (%) to Moist Depth (um) graph in FIG. 10) as measured according to the Moist Towel Surface Structure Test Method described herein.

The wound roll of fibrous structure is then unwound on a Compacted Fibrous Structure Article-making line to convert the fibrous structure to a Compacted Fibrous Structure Article. During the converting operation, a surfactant paste composition comprising a surfactant paste is applied to the fibrous structure to produce a dry fibrous structure (dry paper towel) comprising the surfactant paste composition by any suitable means, for example by spraying and/or slot extruding on the surfactant paste composition to one or more surfaces of the fibrous structure.

The treated fibrous structure is then folded and processed as shown in FIG. 5 to produce a fabric-side-out (FSO) compacted fibrous structure article (compacted paper towel).

In one example, the V-folded fibrous structure 64 is folded upon itself along its axis A to produce a folded-up fibrous structure article 66 by a folding machine 81 as shown in FIG. 12, which may be direct coupled and/or close coupled and/or separate from the process and/or equipment used in the process shown in FIG. 5. As shown in FIG. 12, the folding machine 81 comprises a receiving opening 82 that receives the V-folded fibrous structure 64. The arrows within FIG. 12 show the movement path of the V-folded fibrous structure 64 and further folded-up fibrous structure articles 68. The receiving opening 82 may comprise a pair of rollers and/or a roller and a plate and/or a pair of plates and/or a roller and a belt and/or a plate and a belt and/or a pair of belts 83A and 83B that form a nip between which the V-folded fibrous structure 64 is received and transported by the folding machine 81 to a first fold tuck station 84. After passing by the end of the belts 83A and 83B, the leading portion of the V-folded fibrous structure 64 is drawn into a holding area, for example a tube, for example by way of an air flow induced into the holding area for the purpose of maintaining tension on and controlling the trajectory of the leading portion of the V-folded fibrous structure 64. The first fold tuck station 84 comprises a gap 85 through which a first ram 86 enters to make a first fold tuck in the V-folded fibrous structure 64 to make a further folded-up fibrous structure article 66 with a tab portion 68 and then retracts so that the next V-folded fibrous structure 64 may enter the first fold tuck station 84.

The further folded-up fibrous structure article 66 then moves to a second fold tuck station 87. The second fold tuck station 87 comprises a gap 88 through which a second ram 89 enters to make a second fold tuck in the further folded-up fibrous structure article 66 while retaining the tab portion 68. Next, the second fold tucked further folded-up fibrous structure article 66 then moves to a reorienting station 90 that reorients, for example flips the second fold tucked further folded-up fibrous structure article 66 over 180° so that the previous top is now the bottom and the previous bottom is now the top. This flip causes the extended tab 68 to wrap around the end of the folded-up fibrous structure article 66 with the tab's free end now adjacent to the new top side of the folded-up fibrous structure article 66. Next, the second fold tucked folded-up fibrous structure article 66 exits the folding machine 81 though an exit opening 91. As exemplified in FIG. 5, after exiting the folding machine 81, the second fold tucked folded-up fibrous structure article 66 then enters a mold and piston arrangement 72, which may be part of a mechanical press, as a precursor compacted fibrous structure article 70 and is then subjected to a force, for example from about 10,000 to about 50,000 and/or from about 20,000 to about 40,000 and/or about 30,000 pounds of force and/or a pressure, for example from about 3,000 to about 30,000 and/or from about 5,000 to about 25,000 and/or from about 7,500 to about 20,000 psi, to compress at least a portion, for example a portion of the precursor compacted fibrous structure article 70 such that the compressed and/or higher density and/or lower thickness portion of the resulting compacted fibrous structure article 10 according to the present invention is produced and therefore the compacted fibrous structure article 10 itself is produced.

This compacted fibrous structure article 10 and other compacted fibrous structure articles of the present invention may exhibit a plate stiffness value of less than 300 gf/mm-mm and/or less than 200 gf/mm-mm and/or less than 150 gf/mm-mm and/or less than 100 gf/mm-mm and/or less than 75 gf/mm-mm and/or less than 50 gf/mm-mm and/or less than 30 gf/mm-mm and/or greater than 0 gf/mm-mm and/or greater than 5 gf/mm-mm As shown in FIG. 11, the compacted fibrous structure articles of the present invention (Inv A, B, C) may exhibit lower plate stiffness values than prior art compacted fibrous structure articles.

Example 2 A Dry-to-the Touch Paper Towel Comprising Greater than 20% Synthetic Filaments and Comprising a Surfactant Paste Composition

A 21.%:27.5%47.5%:4% blend of Lyondell-Basell PH835 polypropylene:Lyondell-Basell Metocene MF650W polypropylene:Lyondell-Basell Metocene MF650X:Ampacet 412951 opacifier is dry blended, to form a melt blend. The melt blend is heated to 475° F. through a melt extruder. A 15.5 inch wide Biax 12 row spinnerette with 192 nozzles per cross-direction inch, commercially available from Biax Fiberfilm Corporation, is utilized. 40 nozzles per cross-direction inch of the 192 nozzles have a 0.018 inch inside diameter while the remaining nozzles are solid, i.e. there is no opening in the nozzle. Approximately 0.19 grams per hole per minute (ghm) of the melt blend is extruded from the open nozzles to form meltblown filaments from the melt blend. Approximately 375 SCFM of compressed air, equivalent to a jet-to-melt mass ratio of 22, is heated such that the air exhibits a temperature of about 395° F. at the spinnerette. Approximately 475 g/minute of Golden Isle (from Georgia Pacific) 4825 semi-treated SSK pulp is defibrillated through a hammermill to form SSK wood pulp fibers (solid additive). Air at a temperature of about 85 to 90° F. and about 85% relative humidity (RH) is drawn into the hammermill. Approximately 1200 SCFM of air carries the pulp fibers to a solid additive spreader. The solid additive spreader turns the pulp fibers and distributes the pulp fibers in the cross-direction such that the pulp fibers are injected into the meltblown filaments in a perpendicular fashion (with respect to the flow of the meltblown filaments) through a 4 inch×15 inch cross-direction (CD) slot. A forming box surrounds the area where the meltblown filaments and pulp fibers are commingled. This forming box is designed to reduce the amount of air allowed to enter or escape from this commingling area; however, there is an additional 4 inch×15 inch spreader opposite the solid additive spreader designed to add cooling air. Approximately 1000 SCFM of air at approximately 80° F. is added through this additional spreader. A forming vacuum pulls air through a collection device, such as a patterned belt, thus collecting the commingled meltblown filaments and pulp fibers to form a fibrous structure comprising a pattern of non-random, repeating microregions. The fibrous structure formed by this process comprises about 75% by dry fibrous structure weight of pulp and about 25% by dry fibrous structure weight of meltblown filaments.

A meltblown layer of the meltblown filaments, such as a scrim, is added to both sides of the above formed fibrous structure. This addition of the meltblown layer can help reduce the lint created from the fibrous structure during use by consumers and is preferably performed prior to any thermal bonding operation of the fibrous structure. The two scrim layers can be the same or different than the meltblown filaments in the center formed fibrous structure. To make the meltblown filaments for the exterior layers, A 15.5 inch wide Biax 12 row spinnerette with 192 nozzles per cross-direction inch, commercially available from Biax Fiberfilm Corporation, is utilized. 64 nozzles per cross-direction inch of the 192 nozzles have a 0.018 inch inside diameter while the remaining nozzles are solid, i.e. there is no opening in the nozzle. Approximately 0.21 grams per hole per minute (ghm) of the melt blend is extruded from the open nozzles to form meltblown filaments from the melt blend. Approximately 420 SCFM of compressed air, equivalent to a jet-to-melt mass ratio of 22, is heated such that the air exhibits a temperature of about 395° F. at the spinnerette. A forming vacuum pulls air through a collection device, such as a non-patterned forming belt or through-air-drying fabric, thus collecting the meltblown filaments to form a fibrous structure on top of the above formed fibrous structure.

An additional meltblown layer, such as a scrubbing scrim layer, is added to one side of the above layered fibrous structure. The basis weight and filament diameter of such meltblown layer is important in controlling its surface roughness. The meltblown filaments for this layer can be the same or different than the meltblown filaments used in other layers. To make the meltblown filaments for this scrubbing scrim layer, A 15.5 inch wide Biax 12 row spinnerette with 192 nozzles per cross-direction inch, commercially available from Biax Fiberfilm Corporation, is utilized. 64 nozzles per cross-direction inch of the 192 nozzles have a 0.018 inch inside diameter while the remaining nozzles are solid, i.e. there is no opening in the nozzle. Approximately 0.21 grams per hole per minute (ghm) of the melt blend is extruded from the open nozzles to form meltblown filaments from the melt blend. Approximately 88 SCFM of compressed air, equivalent to a jet-to-melt mass ratio of 4.6, is heated such that the air exhibits a temperature of about 395° F. at the spinnerette. A forming vacuum pulls air through a collection device, such as a non-patterned forming belt or through-air-drying fabric, thus collecting the meltblown filaments to form a fibrous structure on top of the above formed fibrous structure. The fibrous structure is made at a basis weight of from about 70 gsm to about 90 gsm, for example about 81 gsm.

The wound roll of fibrous structure is then unwound on a Compacted Fibrous Structure Article-making line to convert the fibrous structure to a Compacted Fibrous Structure Article. During the converting operation, a surfactant paste composition comprising a surfactant paste is applied to the fibrous structure to produce a dry fibrous structure (dry paper towel) comprising the surfactant paste composition by any suitable means, for example by spraying and/or slot extruding on the surfactant paste composition to one or more surfaces of the fibrous structure.

The treated fibrous structure is then folded and processed as shown in FIG. 5 to produce a compacted fibrous structure article (compacted paper towel).

Test Methods

Unless otherwise specified, all tests described herein including those described under the Definitions section and the following test methods are conducted on samples that have been conditioned in a conditioned room at a temperature of 23° C.±1.0° C. and a relative humidity of 50%±2% for a minimum of 2 hours prior to the test. The samples tested are “usable units.” “Usable units” as used herein means sheets, flats from roll stock, pre-converted flats, and/or single or multi-ply products. All tests are conducted in such conditioned room. Do not test samples that have defects such as wrinkles, tears, holes, and like. All instruments are calibrated according to manufacturer's specifications.

Mass Test Method:

The mass of a compacted/compressed fibrous structure article is measured using a top loading analytical balance with a resolution of ±0.001 g, and is protected from air drafts and other disturbances using a draft shield. Report the mass value to the nearest 0.001 g.

Micro-CT (μCT) Compacted/Compressed Fibrous Structure Article Test Method:

The micro-CT compacted/compressed fibrous structure article measurement test method is utilized to measure the volume of the compacted/compressed fibrous structure article. The volume measurement is based on analysis of polygonal (triangulated point cloud) data generated on a microtomograph (micro-CT) instrument (a suitable instrument is the FlashCT available from Hytec, Los Alamos, N. Mex., or equivalent). To generate the data an x-ray beam is passed through a compacted/compressed fibrous structure article sample mounted on a rotating stage, where some of the x-rays are attenuated by the compacted/compressed fibrous structure article sample. The extent of attenuation correlates to the mass of material the x-rays have to pass through. The transmitted x-rays continue on to the digital detector array and generate a 2D projection image of the compacted/compressed fibrous structure article sample. A 3D image of the compacted/compressed fibrous structure article sample is generated by collecting several individual projection images of the compacted/compressed fibrous structure article sample as it is rotated, which are then reconstructed into a single 3D data set. The instrument is interfaced with a computer running software to control the image acquisition of the raw data (suitable software is ZxAcquire DDA v2.6.7.19698 available from Industrial Imaging Solutions, Santa Clara, Calif., or equivalent). The raw 2D projection data is reconstructed into a 3D image and converted to polygonal data using CT analysis software (a suitable software is efX-CT software v. 1.9.5.1 available from North Star Imaging, Rogers, Minn., or equivalent). The 3D polygonal data set is then analyzed using a 3D metrology software (a suitable software is Geomagic Studio 2014 available from 3D Systems, Rock Hill, S.C., or equivalent).

The FlashCT is a cone beam micro-CT with a shielded walk-in cabinet. A dismountable Viscom microfocus x-ray tube is used as the source with an adjustable diameter focal spot. The transmitted x-rays pass through a collimator, a scintillator (Lanex regular), and onto a 30×40 cm Varian (Paxscan) amorphous silicon digital detector. The x-ray tube is an XT9225-DED with a maximum energy of 225 keV and a current range of 10 μA to 3000 μA. The detector is located 880 mm from the source and runs at 5 frames per second.

The instrument is set up and calibrated according to the manufacturer's specifications. The compacted/compressed fibrous structure compacted/compressed fibrous structure article sample to be scanned is placed on top of a block of low density foam, such as Styrofoam or melamine foam, which will allow the signal from the compacted/compressed fibrous structure article sample to be easily separated from its surroundings for analysis. The foam block and compacted/compressed fibrous structure article sample are mounted onto the instrument's rotary table. Using the instrument control software, the scanning parameters are set to acquire a full 360 degree rotation of 2D projection images. The sample stage is located such that the size of the 3D image field of view contains the entire compacted/compressed fibrous structure article sample, and the final resolution of the reconstructed 3D image has an isotropic voxel resolution of 30 μm (microns). Images are acquired with the x-ray source energy settings optimized to give the best contrast for the given compacted/compressed fibrous structure article sample material, but once optimized held constant for all substantially similar compacted/compressed fibrous structure article samples. For example, the appropriate energy settings for a compacted/compressed fibrous structure article sample may be a voltage setting of 80 kVp and a current setting of 400 μA, with no additional low energy filter. At least 4 averages are collected to obtain a sufficient signal to noise for proper analysis. The raw data is saved in 32-bit floating point format to preserve the full detector output signal for analysis.

Using the CT analysis software, the raw 2D projection data is reconstructed into a 3D image. Once reconstructed, the 3D data set is thresheld at a value which separates, and removes, the background signal due to air and foam, but maintains the signal from the compacted/compressed fibrous structure article sample. The point cloud of the remaining signal from the compacted/compressed fibrous structure article sample is converted into a polygonal mesh and saved in the appropriate 3D file format, such as STL.

The polygonal data of the compacted/compressed fibrous structure article sample is opened in the 3D metrology software, and a closed volume created. Using the 3D metrology software the volume of the compacted/compressed fibrous structure article sample is measured and recorded to the nearest 0.1 cubic mm (mm³).

After scanning a compacted/compressed fibrous structure article sample in the micro-CT, the mass of the compacted/compressed fibrous structure article sample is measured using a top loading analytical balance with a resolution of ±0.001 g, and is protected from air drafts and other disturbances using a draft shield.

The Average Overall Density of a compacted/compressed fibrous structure article is calculated by dividing the mass of the compacted/compressed fibrous structure article by the volume of the compacted/compressed fibrous structure article. Average Overall Density is reported in g/cm³.

For intensive property measurements of a region of a compacted/compressed fibrous structure article, the following steps are performed.

3D Image Processing:

Load the 3D image into image analysis software (suitable image analysis software is MATLAB available from The Mathworks, Inc., Natick, Mass., or Avizo available from Thermo Fisher Scientific, Waltham, Mass., or equivalent) to measure intensive property values of basis weight, thickness and density within a region of the compacted/compressed fibrous structure article sample. The largest cross-sectional area of the sample should be nearly parallel with the x-y plane, with the z-axis being perpendicular. Threshold the 3D image at a value which separates, and removes, the background signal due to air, but maintains the signal from the sample fibers within the compacted/compressed fibrous structure article.

Intensive Property Images:

Five 2D intensive property images are generated from the thresholded 3D image. The first is the Basis Weight Image, which is a projection image. Each x-y pixel in this image represents the summation of the intensity values along voxels in the z-direction. This results in a 2D image where each pixel now has a value equal to the cumulative signal through the entire sample.

The weight (mass) of the whole compacted/compressed fibrous structure article sample divided by the z-direction projected area of the compacted/compressed fibrous structure article sample provides the actual basis weight of the sample. This value is correlated with the signal intensity of Basis Weight image described above, regressed to the origin, allowing it to be represented in units of grams per square meter (gsm).

The second intensive property 2D image is the Thickness Image To generate this image the upper and lower surfaces of the sample are identified, and the distance between these surfaces is calculated giving the sample thickness. The upper surface of the sample is identified by starting at the uppermost z-direction slice and evaluating each slice going through the sample to locate the z-direction voxel for all pixel positions in the xy-plane where sample signal was first detected. The same procedure is followed for identifying the lower surface of the sample, except the z-direction voxels located are all the positions in the xy-plane where sample signal was last detected. Once the upper and lower surfaces have been identified they are smoothed with a 15×15 median filter to remove signal from stray fibers. The 2D Thickness Image is then generated by counting the number of voxels that exist between the upper and lower surfaces for each of the pixel positions in the xy-plane. This raw thickness value is then converted to actual distance, in microns, by multiplying the voxel count by the 6 μm slice thickness resolution.

The third intensive property 2D image is the Density Image To generate this image divide each xy-plane pixel value in the Basis Weight Image, in units of gsm, by the corresponding pixel in the Thickness Image, in units of microns. The units of the Density Image are grams per cubic centimeter (g/cm³).

For each x-y location, the first and last occurrence of a thresholded voxel position in the z-direction is recorded. This provides two sets of points representing the Top Layer and Bottom Layer of the sample. Each set of points are fit to a second-order polynomial to provide smooth top and bottom surfaces. These surfaces define fourth and fifth 2D intensive property images, the top-layer and bottom-layer of the sample. These surfaces are saved as images with the gray values of each pixel representing the z-value of the surface point.

Micro-CT Basis Weight, Thickness and Density Intensive Properties:

Identify the boundary of a region or portion of the compacted/compressed fibrous structure article sample for analysis. Draw the largest circular region of interest that can be inscribed within the region. From each of the first three intensive property images calculate the average basis weight, thickness and density within the region of interest. Record these values as the region's micro-CT basis weight to the nearest 0.01 gsm, micro-CT thickness to the nearest 0.1 micron and micro-CT density to the nearest 0.0001 g/cm³.

Emtec Test Method:

TS7 and TS750 values are measured using an EMTEC Tissue Softness Analyzer (“Emtec TSA”) (Emtec Electronic GmbH, Leipzig, Germany) interfaced with a computer running Emtec TSA software (version 3.19 or equivalent). According to Emtec, the TS7 value correlates with the real material softness, while the TS750 value correlates with the felt smoothness/roughness of the material. The Emtec TSA comprises a rotor with vertical blades which rotate on the test sample at a defined and calibrated rotational speed (set by manufacturer) and contact force of 100 mN. Contact between the vertical blades and the test piece creates vibrations, which create sound that is recorded by a microphone within the instrument. The recorded sound file is then analyzed by the Emtec TSA software. The sample preparation, instrument operation and testing procedures are performed according the instrument manufacture's specifications.

Sample Preparation

Test samples are prepared by cutting square or circular samples from a finished product. Test samples are cut to a length and width (or diameter if circular) of no less than about 90 mm, and no greater than about 120 mm, in any of these dimensions, to ensure the sample can be clamped into the TSA instrument properly. Test samples are selected to avoid perforations, creases or folds within the testing region. Prepare 8 substantially similar replicate samples for testing. Equilibrate all samples at TAPPI standard temperature and relative humidity conditions (23° C.±2 C.° and 50±2%) for at least 1 hour prior to conducting the TSA testing, which is also conducted under TAPPI conditions.

Testing Procedure

Calibrate the instrument according to the manufacturer's instructions using the 1-point calibration method with Emtec reference standards (“ref.2 samples”). If these reference samples are no longer available, use the appropriate reference samples provided by the manufacturer. Calibrate the instrument according to the manufacturer's recommendation and instruction, so that the results will be comparable to those obtained when using the 1-point calibration method with Emtec reference standards (“ref.2 samples”).

Mount the test sample into the instrument, and perform the test according to the manufacturer's instructions. When complete, the software displays values for TS7 and TS750. Record each of these values to the nearest 0.01 dB V² rms. The test piece is then removed from the instrument and discarded. This testing is performed individually on the top surface (outer facing surface of a rolled product) of four of the replicate samples, and on the bottom surface (inner facing surface of a rolled product) of the other four replicate samples.

The four test result values for TS7 and TS750 from the top surface are averaged (using a simple numerical average); the same is done for the four test result values for TS7 and TS750 from the bottom surface. Report the individual average values of TS7 and TS750 for both the top and bottom surfaces on a particular test sample to the nearest 0.01 dB V² rms. Additionally, average together all eight test value results for TS7 and TS750, and report the overall average values for TS7 and TS750 on a particular test sample to the nearest 0.01 dB V² rms.

Basis Weight Test Method:

Basis weight of a fibrous structure and/or sanitary tissue product is measured on stacks of twelve usable units using a top loading analytical balance with a resolution of ±0.001 g. The balance is protected from air drafts and other disturbances using a draft shield. A precision cutting die, measuring 3.500 in±0.0035 in by 3.500 in±0.0035 in is used to prepare all samples.

With a precision cutting die, cut the samples into squares. Combine the cut squares to form a stack twelve samples thick. Measure the mass of the sample stack and record the result to the nearest 0.001 g.

The Basis Weight is calculated in lbs/3000 ft² or g/m² as follows:

Basis Weight=(Mass of stack)/[(Area of 1 square in stack)×(No. of squares in stack)]

For example,

Basis Weight (lbs/3000 ft²)=[[Mass of stack (g)/453.6 (g/lbs)]/[12.25(in²)/144(in²/ft²)×12]]×3000

or,

Basis Weight (g/m²)=Mass of stack (g)/[79.032(cm²)/10,000(cm²/m²)×12]

Report result to the nearest 0.1 lbs/3000 ft² or 0.1 g/m². Sample dimensions can be changed or varied using a similar precision cutter as mentioned above, so as at least 100 square inches of sample area in stack.

Crystallinity Test Method:

The crystallinity of a surfactant composition (aqueous solution of surfactants or a surfactant paste composition), 100 μL of the surfactant composition (33.3 parts surfactant composition and 66.7 parts distilled water) to be tested is added to a glass microscope slide. The slide is left to rest at 25° C. for 7 days to dry and permit any crystallizatine arrangement to occur. A cover slide is then added to the glass microscope slide to sandwich the dried surfactant composition between the glass microscope slide and the cover slide. A standard optical microscope (Nikon 516096 or equivalent) with a 0-360° rotational angle polarizer (Nikon Phase Contrast T-2 15957 or equivalent) was then used to view the surfactant composition. This crystallinity test method identifies surfactant compositions based on type and amount of crystallinity, for example crystal aggregation versus no crystal aggregation, birefringence versus no birefringence.

Caliper Test Method:

Caliper of a fibrous structure and/or sanitary tissue product is measured using a ProGage Thickness Tester (Thwing-Albert Instrument Company, West Berlin, N.J.) with a pressure foot diameter of 2.00 inches (area of 3.14 in²) at a pressure of 95 g/in². Four (4) samples are prepared by cutting of a usable unit such that each cut sample is at least 2.5 inches per side, avoiding creases, folds, and obvious defects. An individual specimen is placed on the anvil with the specimen centered underneath the pressure foot. The foot is lowered at 0.03 in/sec to an applied pressure of 95 g/in². The reading is taken after 3 sec dwell time, and the foot is raised. The measure is repeated in like fashion for the remaining 3 specimens. The caliper is calculated as the average caliper of the four specimens and is reported in mils (0.001 in) to the nearest 0.1 mils.

Moist Towel Surface Structure Test Method:

This test method measures the surface topography of a towel surface, both in a dry and moist state, and calculates the % contact area and the median depth of the lowest 10% of the projected measured area, with the test sample under a specified pressure using a smooth and rigid transparent plate with an anti-reflective coating (to minimize and/or eliminate invalid image pixels).

Condition the samples or useable units of product, with wrapper or packaging materials removed, in a room conditioned at 50±2% relative humidity and 23° C.±1° C. (73°±2° F.) for a minimum of two hours prior to testing. Do not test useable units with defects such as wrinkles, tears, holes, effects of tail seal or core adhesive, etc., and when necessary replace with other useable units free of such defects. Test sample dimensions shall be of the size of the usable unit, removed carefully at the perforations if they are present. If perforations are not present, or for samples larger than 8 inches MD by 11 inches CD, cut the sample to a length of approximately 6 inches in the MD and 11 inches in the CD. In this test only the inside surface of the usable unit(s) is analyzed. The inside surface is identified as the surface oriented toward the interior core when wound on a product roll (i.e., the opposite side of the surface visible on the outside roll as presented to a consumer).

The instrument used in this method is a Gocator 3210 Snapshot System (LMI Technologies, Inc., 9200 Glenlyon Parkway, Burnaby, BC V5J 5J8 Canada), or equivalent. This instrument is an optical 3D surface topography measurement system that measures the surface height of a sample using a projected structured light pattern technique. The result of the measurement is a topography map of surface height (z-directional or z-axis) versus displacement in the x-y plane. This particular system has a field of view of approximately 100×154 mm, however the captured images are cropped to 80×130 mm (from the center) prior to analysis. The system has an x-y pixel resolution of 86 microns. The clearance distance from the camera to the testing surface (which is smooth and flat, and perpendicular to the camera view) is 23.5 (+/−0.2) cm—see FIG. 13. Calibration plates can be used to verify that the system is accurate to manufacturer's specifications. The system is set to a Brightness value of 7, and a Dynamic value of 3, in order to most accurately capture the surface topography and minimize non-measured pixels and noise. Other camera settings may be used, with the objective of most accurately measuring the surface topography, while minimizing the number of invalid and non-measurable points.

Test samples are handled only at their corners. The test sample is first weighted on a scale with at least 0.001 gram accuracy, and its dry weight recorded to the nearest 0.01 gram. It is then placed on the testing surface, with its inside face oriented towards the Gocator camera, and centered with respect to the imaging view. A smooth and rigid transparent plate (8×10 inches) is gently placed on top of the test sample, centered with respect to its x-y dimensions. Equal size weights are placed on the four corners of the transparent plate such that they are close to the four corners of the projected imaged area, but do not interfere in any way with the measurement image. The size of each equal sized weight is such that the total weight of transparent plate and the four weights delivers a total pressure of 25 (+/−1) grams per square inch (gsi) to the test sample under the plate. Within 15 seconds of placing the four weights in their proper position, the Gocator system is then initiated to acquire the topography image of the test sample in its ‘dry’ state.

Immediately after saving the Gocator image of the ‘dry’ state image, the weights and plate are removed from the test sample. The test sample is then moved to a smooth, clean countertop surface, with its inside face still up. Using a pipette, 15-30 ml of deionized water is distributed evenly across the entire surface of the test sample until it is visibly apparent that the water has fully wetted the entire test sample, and no unwetted area is observed. The wetting process is to be completed in less than a minute. The wet test sample is then gently picked up by two adjacent corners, so that it hangs freely (dripping may occur), and carefully placed on a sheet of blotter paper (Whatman cellulose blotting paper, grade GB003, cut to dimensions larger than the test sample). The wet test sample must be placed flat on the blotting paper without wrinkles or folds present. A smooth, 304 stainless steel cylindrical rod (density of ˜8 g/cm³), with dimensions of 1.75 inch diameter and 12 inches long, is then rolled over the entire test sample at a speed of 1.5-2.0 inches per second, in the direction of the shorter of the two dimensions of the test sample. If creases or folds are created during the rolling process, and are inside the central area of the sample to be measured (i.e., if they cannot slightly adjusted or avoided in the topography measurement), then the test sample is to be discarded for a new test sample, and the measurement process started over. Otherwise, the moist sample is picked up by two adjacent corners and weighed on the scale to the nearest 0.01 gram (i.e., its moist weight). At this point, the moist test paper towel test sample will have a moisture level between 1.25 and 2.00 grams H₂O per gram of initial dry material.

The moist test sample is then placed flat on the Gocator testing surface (handling it carefully, only touching its corners), with its inside surface pointing towards the Gocator camera, and centered with respect to the imaging view (as close to the same position it was for the ‘dry’ state image). After ensuring that the sample is flat, and no folds or creases are present in the imaging area, the smooth and rigid transparent plate (8×10 inches) is gently placed on top of the test sample, centered with respect to its x-y dimensions. The equal size weights are placed on the four corners of the transparent plate (i.e., the same weights that were used in the dry sample testing) such that they are close to the four corners of the projected imaged area, but do not interfere in any way with the measurement image. Within 15 seconds of placing the four weights in their proper position, the Gocator system is then initiated to acquire the topography image of the test sample in its ‘moist’ state.

At this point, the test sample has both ‘dry’ and ‘moist’ surface topography (3D) images. These are processed using surface texture analysis software such as MountainsMap® (available from Digital Surf, France) or equivalent, as follows: 1) The first step is to crop the image. As stated previously, this particular system has a field of view of approximately 100×154 mm, however the image is cropped to 80×130 mm (from the center). 2) Remove ‘invalid’ and non-measured points. 3) Apply a 3×3 median filter (to reduce effects of noise). 4) Apply an ‘Align’ filter, which subtracts a least squares plane to level the surface (to create an overall average of heights centered at zero). 5) Apply a Gaussian filter (according to ISO 16610-61) with a nesting index (cut-off wavelength) of 25 mm (to flatten out large scale waviness, while preserving finer structure).

From these processed 3D images of the surface, the following parameters are calculated, using software such as MountainsMap® or equivalent: Dry Depth (um), Dry Contact Area (%), Moist Depth (um), and Moist Contact Area (%).

Height measurements are derived from the Areal Material Ratio (Abbott-Firestone) curve described in the ISO 13565-2:1996 standard extrapolated to surfaces. This curve is the cumulative curve of the surface height distribution histogram versus the range of surface heights measured. A material ratio is the ratio, expressed as a percent, of the area corresponding to points with heights equal to or above an intersecting plane passing through the surface at a given height, or cut depth, to the cross-sectional area of the evaluation region (field of view area). For calculating contact area, the height at a material ratio of 2% is first identified. A cut depth of 100 μm below this height is then identified, and the material ratio at this depth is recorded as the “Dry Contact Area” and “Moist Contact Area”, respectively, to the nearest 0.1%.

In order to calculate “Depth” (Dry and Moist, respectively), the depth at the 95% material ratio relative to the mean plane (centered height data) of the specimen surface is identified. This corresponds to a depth equal to the median of the lowest 10% of the projected area (valleys) of the specimen surface and is recorded as the “Dry Depth” and “Moist Depth”, respectively, to the nearest 1 micron (um). These values will be negative as they represent depths below the mean plane of the surface heights having a value of zero.

Three replicate samples are prepared and measured in this way, to produce an average for each of the four parameters: Dry Depth (um), Dry Contact Area (%), Moist Depth (um), and Moist Contact Area (%). Additionally, from these parameters, the difference between the dry and moist depths can be calculated to demonstrate the change in depth from the dry to the moist state.

Thickness Test Method:

Thickness of a compacted fibrous structure article may be measured by any suitable method so long as the measurement is conducted at about 0 g/cm². In one example, the thickness of a compacted fibrous structure article may be measured using a ruler with mm units. In another example, the thickness of a compacted fibrous structure article may be measured using a caliper tool with mm units. The result is reported in millimeters (mm).

Density Test Method:

The density of a fibrous structure and/or sanitary tissue product is calculated as the quotient of the Basis Weight of a fibrous structure or sanitary tissue product expressed in lbs/3000 ft² divided by the Caliper (at 95 g/in²) of the fibrous structure or sanitary tissue product expressed in mils. The final Density value is calculated in lbs/ft³ and/or g/cm³, by using the appropriate converting factors.

SST Absorbency Rate Test Method:

This test incorporates the Slope of the Square Root of Time (SST) Test Method. The SST method measures rate over a wide spectrum of time to capture a view of the product pick-up rate over the useful lifetime. In particular, the method measures the absorbency rate via the slope of the mass versus the square root of time from 2-15 seconds.

Overview

The absorption (wicking) of water by a fibrous sample is measured over time. A sample is placed horizontally in the instrument and is supported with minimal contact during testing (without allowing the sample to droop) by an open weave net structure that rests on a balance. The test is initiated when a tube connected to a water reservoir is raised and the meniscus makes contact with the center of the sample from beneath, at a small negative pressure. Absorption is controlled by the ability of the sample to pull the water from the instrument for approximately 20 seconds. Rate is determined as the slope of the regression line of the outputted weight vs sqrt(time) from 2 to 15 seconds.

Apparatus

Conditioned Room—Temperature is controlled from 73° F.±2° F. (23° C.±1° C.). Relative Humidity is controlled from 50%±2%

Sample Preparation—Product samples are cut using hydraulic/pneumatic precision cutter into 3.375 inch diameter circles.

Capacity Rate Tester (CRT)—The CRT is an absorbency tester capable of measuring capacity and rate. The CRT consists of a balance (0.001 g), on which rests on a woven grid (using nylon monofilament line having a 0.014″ diameter) placed over a small reservoir with a delivery tube in the center. This reservoir is filled by the action of solenoid valves, which help to connect the sample supply reservoir to an intermediate reservoir, the water level of which is monitored by an optical sensor. The CRT is run with a −2 mm water column, controlled by adjusting the height of water in the supply reservoir.

A diagram of the testing apparatus set up is shown in FIG. 14.

Software—LabView based custom software specific to CRT Version 4.2 or later.

Water—Distilled water with conductivity <10 μS/cm (target <5 μS/cm) @ 25° C.

Sample Preparation

For this method, a usable unit is described as one finished product unit regardless of the number of plies. Condition all samples with packaging materials removed for a minimum of 2 hours prior to testing. Discard at least the first ten usable units from the roll. Remove two usable units and cut one 3.375-inch circular sample from the center of each usable unit for a total of 2 replicates for each test result. Do not test samples with defects such as wrinkles, tears, holes, etc. Replace with another usable unit which is free of such defects

Sample Testing

Pre-Test Set-Up

-   -   1. The water height in the reservoir tank is set −2.0 mm below         the top of the support rack (where the towel sample will be         placed).     -   2. The supply tube (8 mm I.D.) is centered with respect to the         support net.     -   3. Test samples are cut into circles of 3⅜″ diameter and         equilibrated at Tappi environment conditions for a minimum of 2         hours.

Test Description

-   -   1. After pressing the start button on the software application,         the supply tube moves to 0.33 mm below the water height in the         reserve tank. This creates a small meniscus of water above the         supply tube to ensure test initiation. A valve between the tank         and the supply tube closes, and the scale is zeroed.     -   2. The software prompts you to “load a sample”. A sample is         placed on the support net, centering it over the supply tube,         and with the side facing the outside of the roll placed         downward.     -   3. Close the balance windows and press the “OK” button—the         software records the dry weight of the circle.     -   4. The software prompts you to “place cover on sample”. The         plastic cover is placed on top of the sample, on top of the         support net. The plastic cover has a center pin (which is flush         with the outside rim) to ensure that the sample is in the proper         position to establish hydraulic connection. Four other pins, 1         mm shorter in depth, are positioned 1.25-1.5 inches radially         away from the center pin to ensure the sample is flat during the         test. The sample cover rim should not contact the sheet. Close         the top balance window and click “OK”.     -   5. The software re-zeroes the scale and then moves the supply         tube towards the sample. When the supply tube reaches its         destination, which is 0.33 mm below the support net, the valve         opens (i.e., the valve between the reserve tank and the supply         tube), and hydraulic connection is established between the         supply tube and the sample. Data acquisition occurs at a rate of         5 Hz and is started about 0.4 seconds before water contacts the         sample.     -   6. The test runs for at least 20 seconds. After this, the supply         tube pulls away from the sample to break the hydraulic         connection.     -   7. The wet sample is removed from the support net. Residual         water on the support net and cover are dried with a paper towel.     -   8. Repeat until all samples are tested.     -   9. After each test is run, a *.txt file is created (typically         stored in the CRT/data/rate directory) with a file name as typed         at the start of the test. The file contains all the test set-up         parameters, dry sample weight, and cumulative water absorbed (g)         vs. time (sec) data collected from the test.

Calculation of Rate of Uptake

Take the raw data file that includes time and weight data.

First, create a new time column that subtracts 0.4 seconds from the raw time data to adjust the raw time data to correspond to when initiation actually occurs (about 0.4 seconds after data collection begins).

Second, create a column of data that converts the adjusted time data to square root of time data (e.g., using a formula such as SQRT( ) within Excel).

Third, calculate the slope of the weight data vs the square root of time data (e.g., using the SLOPE( ) function within Excel, using the weight data as the y-data and the sqrt(time) data as the x-data, etc.). The slope should be calculated for the data points from 2 to 15 seconds, inclusive (or 1.41 to 3.87 in the sqrt(time) data column)

Calculation of Slope of the Square Root of Time (SST)

The start time of water contact with the sample is estimated to be 0.4 seconds after the start of hydraulic connection is established between the supply tube and the sample (CRT Time). This is because data acquisition begins while the tube is still moving towards the sample and incorporates the small delay in scale response. Thus, “time zero” is actually at 0.4 seconds in CRT Time as recorded in the *.txt file.

The slope of the square root of time (SST) from 2-15 seconds is calculated from the slope of a linear regression line from the square root of time between (and including) 2 to 15 seconds (x-axis) versus the cumulative grams of water absorbed. The units are g/sec^(0.5).

Reporting Results

Report the average slope to the nearest 0.01 g/s^(0.5).

Plate Stiffness Test Method:

As used herein, the “Plate Stiffness” test is a measure of stiffness of a flat sample as it is deformed downward into a hole beneath the sample. For the test, the sample is modeled as an infinite plate with thickness “t” that resides on a flat surface where it is centered over a hole with radius “R”. A central force “F” applied to the tissue directly over the center of the hole deflects the tissue down into the hole by a distance “w”. For a linear elastic material, the deflection can be predicted by:

$w = {\frac{3F}{4\pi{Et}^{3}}\left( {1 - v} \right)\left( {3 + v} \right)R^{2}}$

where “E” is the effective linear elastic modulus, “v” is the Poisson's ratio, “R” is the radius of the hole, and “t” is the thickness of the tissue, taken as the caliper in millimeters measured on a stack of 5 tissues under a load of about 0.29 psi. Taking Poisson's ratio as 0.1 (the solution is not highly sensitive to this parameter, so the inaccuracy due to the assumed value is likely to be minor), the previous equation can be rewritten for “w” to estimate the effective modulus as a function of the flexibility test results:

$E \approx {\frac{3R^{2}}{4t^{3}}\frac{F}{w}}$

The test results are carried out using an MTS Alliance RT/1, Insight Renew, or similar model testing machine (MTS Systems Corp., Eden Prairie, Minn.), with a 50 newton load cell, and data acquisition rate of at least 25 force points per second. As a stack of five tissue sheets (created without any bending, pressing, or straining) at least 2.5-inches by 2.5 inches, but no more than 5.0 inches by 5.0 inches, oriented in the same direction, sits centered over a hole of radius 15.75 mm on a support plate, a blunt probe of 3.15 mm radius descends at a speed of 20 mm/min. For typical perforated rolled bath tissue, sample preparation consists of removing five (5) connected usable units, and carefully forming a 5 sheet stack, accordion style, by bending only at the perforation lines. When the probe tip descends to 1 mm below the plane of the support plate, the test is terminated. The maximum slope (using least squares regression) in grams of force/mm over any 0.5 mm span during the test is recorded (this maximum slope generally occurs at the end of the stroke). The load cell monitors the applied force and the position of the probe tip relative to the plane of the support plate is also monitored. The peak load is recorded, and “E” is estimated using the above equation.

The Plate Stiffness “S” per unit width can then be calculated as:

$S = \frac{{Er}^{3}}{12}$

and is expressed in units of Newtons*millimeters. The Testworks program uses the following formula to calculate stiffness (or can be calculated manually from the raw data output):

$S = {\left( \frac{F}{w} \right)\left\lbrack \frac{\left( {3 + v} \right)R^{2}}{16\pi} \right\rbrack}$

wherein “F/w” is max slope (force divided by deflection), “v” is Poisson's ratio taken as 0.1, and “R” is the ring radius.

The same sample stack (as used above) is then flipped upside down and retested in the same manner as previously described. This test is run three more times (with different sample stacks). Thus, eight S values are calculated from four 5-sheet stacks of the same sample. The numerical average of these eight S values is reported as Plate Stiffness for the sample.

Stack Compressibility and Resilient Bulk Test Method:

Stack thickness (measured in mils, 0.001 inch) is measured as a function of confining pressure (g/in²) using a Thwing-Albert (14 W. Collings Ave., West Berlin, N.J.) Vantage Compression/Softness Tester (model 1750-2005 or similar) or equivalent instrument, equipped with a 2500 g load cell (force accuracy is +/−0.25% when measuring value is between 10%-100% of load cell capacity, and 0.025% when measuring value is less than 10% of load cell capacity), a 1.128 inch diameter steel pressure foot (one square inch cross sectional area) which is aligned parallel to the steel anvil (2.5 inch diameter). The pressure foot and anvil surfaces must be clean and dust free, particularly when performing the steel-to-steel test. Thwing-Albert software (MAP) controls the motion and data acquisition of the instrument.

The instrument and software are set-up to acquire crosshead position and force data at a rate of 50 points/sec. The crosshead speed (which moves the pressure foot) for testing samples is set to 0.20 inches/min (the steel-to-steel test speed is set to 0.05 inches/min). Crosshead position and force data are recorded between the load cell range of approximately 5 and 1500 grams during compression. The crosshead is programmed to stop immediately after surpassing 1500 grams, record the thickness at this pressure (termed T_(max)), and immediately reverse direction at the same speed as performed in compression. Data is collected during this decompression portion of the test (also termed recovery) between approximately 1500 and 5 grams. Since the foot area is one square inch, the force data recorded corresponds to pressure in units of g/in². The MAP software is programmed to the select 15 crosshead position values (for both compression and recovery) at specific pressure trap points of 10, 25, 50, 75, 100, 125, 150, 200, 300, 400, 500, 600, 750, 1000, and 1250 g/in² (i.e., recording the crosshead position of very next acquired data point after the each pressure point trap is surpassed). In addition to these 30 collected trap points, T_(max) is also recorded, which is the thickness at the maximum pressure applied during the test (approximately 1500 g/in²).

Since the overall test system, including the load cell, is not perfectly rigid, a steel-to-steel test is performed (i.e., nothing in between the pressure foot and anvil) at least twice for each batch of testing, to obtain an average set of steel-to-steel crosshead positions at each of the 31 trap points described above. This steel-to-steel crosshead position data is subtracted from the corresponding crosshead position data at each trap point for each tested stacked sample, thereby resulting in the stack thickness (mils) at each pressure trap point during the compression, maximum pressure, and recovery portions of the test.

StackT(trap)=StackCP(trap)−SteelCP(trap)

Where:

trap=trap point pressure at either compression, recovery, or max

StackT=Thickness of Stack (at trap pressure)

StackCP=Crosshead position of Stack in test (at trap pressure)

SteelCP=Crosshead position of steel-to-steel test (at trap pressure)

A stack of five (5) usable units thick is prepared for testing as follows. The minimum usable unit size is 2.5 inch by 2.5 inch; however a larger sheet size is preferable for testing, since it allows for easier handling without touching the central region where compression testing takes place. For typical perforated rolled bath tissue, this consists of removing five (5) sets of 3 connected usable units. In this case, testing is performed on the middle usable unit, and the outer 2 usable units are used for handling while removing from the roll and stacking. For other product formats, it is advisable, when possible, to create a test sheet size (each one usable unit thick) that is large enough such that the inner testing region of the created 5 usable unit thick stack is never physically touched, stretched, or strained, but with dimensions that do not exceed 14 inches by 6 inches.

The 5 sheets (one usable unit thick each) of the same approximate dimensions, are placed one on top the other, with their MD aligned in the same direction, their outer face all pointing in the same direction, and their edges aligned +/−3 mm of each other. The central portion of the stack, where compression testing will take place, is never to be physically touched, stretched, and/or strained (this includes never to ‘smooth out’ the surface with a hand or other apparatus prior to testing).

The 5 sheet stack is placed on the anvil, positioning it such that the pressure foot will contact the central region of the stack (for the first compression test) in a physically untouched spot, leaving space for a subsequent (second) compression test, also in the central region of the stack, but separated by ¼ inch or more from the first compression test, such that both tests are in untouched, and separated spots in the central region of the stack. From these two tests, an average crosshead position of the stack at each trap pressure (i.e., StackCP(trap)) is calculated for compression, maximum pressure, and recovery portions of the tests. Then, using the average steel-to-steel crosshead trap points (i.e., SteelCP(trap)), the average stack thickness at each trap (i.e., StackT(trap) is calculated (mils).

Stack Compressibility is defined here as the absolute value of the linear slope of the stack thickness (mils) as a function of the log(10) of the confining pressure (grams/in²), by using the 15 compression trap points discussed previously (i.e., compression from 10 to 1250 g/in²), in a least squares regression. The units for Stack Compressibility are [mils/(log(g/in²))], and is reported to the nearest 0.1 [mils/(log(g/in²))].

Resilient Bulk is calculated from the stack weight per unit area and the sum of 8 StackT(trap) thickness values from the maximum pressure and recovery portion of the tests: i.e., at maximum pressure (T_(max)) and recovery trap points at R1250, R1000, R750, R500, R300, R100, and R10 g/in² (a prefix of “R” denotes these traps come from recovery portion of the test). Stack weight per unit area is measured from the same region of the stack contacted by the compression foot, after the compression testing is complete, by cutting a 3.50 inch square (typically) with a precision die cutter, and weighing on a calibrated 3-place balance, to the nearest 0.001 gram. The weight of the precisely cut stack, along with the StackT(trap) data at each required trap pressure (each point being an average from the two compression/recovery tests discussed previously), are used in the following equation to calculate Resilient Bulk, reported in units of cm³/g, to the nearest 0.1 cm³/g.

${{Resilient}{Bulk}} = \frac{{{SUM}\left( {{Stack}{T\left( {T_{\max},{R1250},{R1000},{R750},{R500},{R300},{R100},{R10}} \right)}} \right)}*0.00254}{M/A}$

Where:

StackT=Thickness of Stack (at trap pressures of T_(max) and recovery pressures listed above), (mils)

M=weight of precisely cut stack, (grams)

A=area of the precisely cut stack, (cm²)

Wet Burst Test Method:

“Wet Burst Strength” as used herein is a measure of the ability of a fibrous structure and/or a fibrous structure product incorporating a fibrous structure to absorb energy, when wet and subjected to deformation normal to the plane of the fibrous structure and/or fibrous structure product. The Wet Burst Test is run according to ISO 12625-9:2005, except for any deviations or modifications described below.

Wet burst strength may be measured using a Thwing-Albert Burst Tester Cat. No. 177 equipped with a 2000 g load cell commercially available from Thwing-Albert Instrument Company, Philadelphia, Pa., or an equivalent instrument.

Wet burst strength is measured by preparing four (4) multi-ply fibrous structure product samples for testing. First, condition the samples for two (2) hours at a temperature of 73° F.±2° F. (23° C.±1° C.) and a relative humidity of 50% (±2%). Take one sample and horizontally dip the center of the sample into a pan filled with about 25 mm of room temperature distilled water. Leave the sample in the water four (4) (±0.5) seconds. Remove and drain for three (3) (±0.5) seconds holding the sample vertically so the water runs off in the cross-machine direction. Proceed with the test immediately after the drain step.

Place the wet sample on the lower ring of the sample holding device of the Burst Tester with the outer surface of the sample facing up so that the wet part of the sample completely covers the open surface of the sample holding ring. If wrinkles are present, discard the samples and repeat with a new sample. After the sample is properly in place on the lower sample holding ring, turn the switch that lowers the upper ring on the Burst Tester. The sample to be tested is now securely gripped in the sample holding unit. Start the burst test immediately at this point by pressing the start button on the Burst Tester. A plunger will begin to rise (or lower) toward the wet surface of the sample. At the point when the sample tears or ruptures, report the maximum reading. The plunger will automatically reverse and return to its original starting position. Repeat this procedure on three (3) more samples for a total of four (4) tests, i.e., four (4) replicates. Report the results as an average of the four (4) replicates, to the nearest gram.

Wet Tensile Test Method:

Wet Elongation, Tensile Strength, and TEA are measured on a constant rate of extension tensile tester with computer interface (a suitable instrument is the EJA Vantage from the Thwing-Albert Instrument Co. West Berlin, N.J.) using a load cell for which the forces measured are within 10% to 90% of the limit of the load cell. Both the movable (upper) and stationary (lower) pneumatic jaws are fitted with smooth stainless steel faced grips, with a design suitable for testing 1 inch wide sheet material (Thwing-Albert item #733GC). An air pressure of about 60 psi is supplied to the jaws.

Eight usable units of fibrous structures are divided into two stacks of four usable units each. The usable units in each stack are consistently oriented with respect to machine direction (MD) and cross direction (CD). One of the stacks is designated for testing in the MD and the other for CD. Using a one inch precision cutter (Thwing Albert) take a CD stack and cut one, 1.00 in ±0.01 in wide by at least 3.0 in long stack of strips (long dimension in CD). In like fashion cut the remaining stack in the MD (strip long dimension in MD), to give a total of 8 specimens, four CD and four MD strips. Each strip to be tested is one usable unit thick, and will be treated as a unitary specimen for testing.

Program the tensile tester to perform an extension test (described below), collecting force and extension data at an acquisition rate of 100 Hz as the crosshead raises at a rate of 2.00 in/min (10.16 cm/min) until the specimen breaks. The break sensitivity is set to 50%, i.e., the test is terminated when the measured force drops below 50% of the maximum peak force, after which the crosshead is returned to its original position.

Set the gage length to 2.00 inches. Zero the crosshead and load cell. Insert the specimen into the upper and lower open grips such that at least 0.5 inches of specimen length is contained each grip. Align the specimen vertically within the upper and lower jaws, then close the upper grip. Verify the specimen is hanging freely and aligned with the lower grip, then close the lower grip. Initiate the first portion of the test, which pulls the specimen at a rate of 0.5 in/min, then stops immediately after a load of 10 grams is achieved. Using a pipet, thoroughly wet the specimen with DI water to the point where excess water can be seen pooling on the top of the lower closed grip Immediately after achieving this wetting status, initiate the second portion of the test, which pulls the wetted strip at 2.0 in/min until break status is achieved. Repeat testing in like fashion for all four CD and four MD specimens.

Program the software to calculate the following from the constructed force (g) verses extension (in) curve:

Wet Tensile Strength (g/in) is the maximum peak force (g) divided by the specimen width (1 in), and reported as g/in to the nearest 0.1 g/in.

Adjusted Gage Length (in) is calculated as the extension measured (from original 2.00 inch gage length) at 3 g of force during the test following the wetting of the specimen (or the next data point after 3 g force) added to the original gage length (in). If the load does not fall below 3 g force during the wetting procedure, then the adjusted gage length will be the extension measured at the point the test is resumed following wetting added to the original gage length (in).

Wet Peak Elongation (%) is calculated as the additional extension (in) from the Adjusted Gage Length (in) at the maximum peak force point (more specifically, at the last maximum peak force point, if there is more than one) divided by the Adjusted Gage Length (in) multiplied by 100 and reported as % to the nearest 0.1%.

Wet Peak Tensile Energy Absorption (TEA, g*in/in²) is calculated as the area under the force curve (g*in²) integrated from zero extension (i.e., the Adjusted Gage Length) to the extension at the maximum peak force elongation point (more specifically, at the last maximum peak force point, if there is more than one) (in), divided by the product of the adjusted Gage Length (in) and specimen width (in). This is reported as g*in/in² to the nearest 0.01 g*in/in².

The Wet Tensile Strength (g/in), Wet Peak Elongation (%), Wet Peak TEA (g*in/in² are calculated for the four CD specimens and the four MD specimens. Calculate an average for each parameter separately for the CD and MD specimens.

Calculations

Geometric Mean Initial Wet Tensile Strength=Square Root of [MD Wet Tensile Strength (g/in)×CD Wet Tensile Strength (Win)]

Geometric Mean Wet Peak Elongation=Square Root of [MD Wet Peak Elongation (%)×CD Wet Peak Elongation (%)]

Geometric Mean Wet Peak TEA=Square Root of [MD Wet Peak TEA (g*in/in²)×CD Wet Peak TEA (g*in/in²)]

Total Wet Tensile (TWT)=MD Wet Tensile Strength (g/in)+CD Wet Tensile Strength (g/in)

Total Wet Peak TEA=MD Wet Peak TEA (g*in/in²)+CD Wet Peak TEA (g*in/in²)

Wet Tensile Ratio=MD Wet Peak Tensile Strength (g/in)/CD Wet Peak Tensile Strength (g/in)

Wet Tensile Geometric Mean (GM) Modulus=Square Root of [MD Modulus (at 38 g/cm)×CD Modulus (at 38 g/cm)]

Dry Elongation, Tensile Strength, TEA and Modulus Test Methods:

Remove five (5) strips of four (4) usable units (also referred to as sheets) of fibrous structures and stack one on top of the other to form a long stack with the perforations between the sheets coincident. Identify sheets 1 and 3 for machine direction tensile measurements and sheets 2 and 4 for cross direction tensile measurements. Next, cut through the perforation line using a paper cutter (JDC-1-10 or JDC-1-12 with safety shield from Thwing-Albert Instrument Co. of Philadelphia, Pa.) to make 4 separate stacks. Make sure stacks 1 and 3 are still identified for machine direction testing and stacks 2 and 4 are identified for cross direction testing.

Cut two 1 inch (2.54 cm) wide strips in the machine direction from stacks 1 and 3. Cut two 1 inch (2.54 cm) wide strips in the cross direction from stacks 2 and 4. There are now four 1 inch (2.54 cm) wide strips for machine direction tensile testing and four 1 inch (2.54 cm) wide strips for cross direction tensile testing. For these finished product samples, all eight 1 inch (2.54 cm) wide strips are five usable units (sheets) thick.

For the actual measurement of the elongation, tensile strength, TEA and modulus, use a Thwing-Albert Intelect II Standard Tensile Tester (Thwing-Albert instrument Co. of Philadelphia, Pa.). Insert the flat face clamps into the unit and calibrate the tester according to the instructions given in the operation manual of the Thwing-Albert Intelect II. Set the instrument crosshead speed to 4.00 in/min (10.16 cm/min) and the 1st and 2nd gauge lengths to 2.00 inches (5.08 cm). The break sensitivity is set to 20.0 grams and the sample width is set to 1.00 inch (2.54 cm) and the sample thickness is set to 0.3937 inch (1 cm). The energy units are set to TEA and the tangent modulus (Modulus) trap setting is set to 38.1 g.

Take one of the fibrous structure sample strips and place one end of it in one damp of the tensile tester. Place the other end of the fibrous structure sample strip in the other clamp. Make sure the long dimension of the fibrous structure sample strip is running parallel to the sides of the tensile tester. Also make sure the fibrous structure sample strips are not overhanging to the either side of the two clamps. in addition, the pressure of each of the damps must be in full contact with the fibrous structure sample strip.

After inserting the fibrous structure sample strip into the two clamps, the instrument tension can be monitored. If it shows a value of 5 grams or more, the fibrous structure sample strip is too taut. Conversely, if a period of 2-3 seconds passes after starting the test before any value is recorded, the fibrous structure sample strip is too slack.

Start the tensile tester as described in the tensile tester instrument manual. The test is complete after the crosshead automatically returns to its initial starting position. When the test is complete, read and record the following with units of measure:

-   Peak Load Tensile (Tensile Strength) (g/in) -   Peak Elongation (Elongation) (%) -   Peak TEA (TEA) (in-g/in²) -   Tangent Modulus (Modulus) (at 15 g/cm) -   Test each of the samples in the same manner, recording the above     measured values from each test.

Calculations:

Geometric Mean (GM) Dry Elongation=Square Root of [MD Elongation (%)×CD Elongation (%)]

Total Dry Tensile (TDT)=Peak Load MD Tensile (g/in)+Peak Load CD Tensile (g/in)

Dry Tensile Ratio=Peak Load MD Tensile (g/in)/Peak Load CD Tensile (g/in)

Geometric Mean (GM) Dry Tensile=[Square Root of (Peak Load MD Tensile (g/in)×Peak Load CD Tensile (g/in))]

Dry TEA=MD TEA (in-g/in²)+CD TEA (in-g/in²)

Geometric Mean (GM) Dry TEA=Square Root of [MD TEA (in-g/in²)×CD TEA (in-g/in²)]

Dry Modulus=MD Modulus (at 15 g/cm)+CD Modulus (at 15 g/cm)

Geometric Mean (GM) Dry Modulus=Square Root of [MD Modulus (at 15 g/cm)×CD Modulus (at 15 g/cm)]

Flexural Rigidity Test Method:

This test is performed on 1 inch×6 inch (2.54 cm×15.24 cm) strips of a fibrous structure sample. A Cantilever Bending Tester such as described in ASTM Standard D 1388 (Model 5010, Instrument Marketing Services, Fairfield, N.J.) is used and operated at a ramp angle of 41.5±0.5° and a sample slide speed of 0.5±0.2 in/second (1.3±0.5 cm/second). A minimum of n=16 tests are performed on each sample from n=8 sample strips.

No fibrous structure sample which is creased, bent, folded, perforated, or in any other way weakened should ever be tested using this test. A non-creased, non-bent, non-folded, non-perforated, and non-weakened in any other way fibrous structure sample should be used for testing under this test.

From one fibrous structure sample of about 4 inch×6 inch (10.16 cm×15.24 cm), carefully cut using a 1 inch (2.54 cm) JDC Cutter (available from Thwing-Albert Instrument Company, Philadelphia, Pa.) four (4) 1 inch (2.54 cm) wide by 6 inch (15.24 cm) long strips of the fibrous structure in the MD direction. From a second fibrous structure sample from the same sample set, carefully cut four (4) 1 inch (2.54 cm) wide by 6 inch (15.24 cm) long strips of the fibrous structure in the CD direction. It is important that the cut be exactly perpendicular to the long dimension of the strip. In cutting non-laminated two-ply fibrous structure strips, the strips should be cut individually. The strip should also be free of wrinkles or excessive mechanical manipulation which can impact flexibility. Mark the direction very lightly on one end of the strip, keeping the same surface of the sample up for all strips. Later, the strips will be turned over for testing, thus it is important that one surface of the strip be clearly identified, however, it makes no difference which surface of the sample is designated as the upper surface.

Using other portions of the fibrous structure (not the cut strips), determine the basis weight of the fibrous structure sample in lbs/3000 ft² and the caliper of the fibrous structure in mils (thousandths of an inch) using the standard procedures disclosed herein. Place the Cantilever Bending Tester level on a bench or table that is relatively free of vibration, excessive heat and most importantly air drafts. Adjust the platform of the Tester to horizontal as indicated by the leveling bubble and verify that the ramp angle is at 41.5±0.5°. Remove the sample slide bar from the top of the platform of the Tester. Place one of the strips on the horizontal platform using care to align the strip parallel with the movable sample slide. Align the strip exactly even with the vertical edge of the Tester wherein the angular ramp is attached or where the zero mark line is scribed on the Tester. Carefully place the sample slide bar back on top of the sample strip in the Tester. The sample slide bar must be carefully placed so that the strip is not wrinkled or moved from its initial position.

Move the strip and movable sample slide at a rate of approximately 0.5±0.2 in/second (1.3±0.5 cm/second) toward the end of the Tester to which the angular ramp is attached. This can be accomplished with either a manual or automatic Tester. Ensure that no slippage between the strip and movable sample slide occurs. As the sample slide bar and strip project over the edge of the Tester, the strip will begin to bend, or drape downward. Stop moving the sample slide bar the instant the leading edge of the strip falls level with the ramp edge. Read and record the overhang length from the linear scale to the nearest 0.5 mm Record the distance the sample slide bar has moved in cm as overhang length. This test sequence is performed a total of eight (8) times for each fibrous structure in each direction (MD and CD). The first four strips are tested with the upper surface as the fibrous structure was cut facing up. The last four strips are inverted so that the upper surface as the fibrous structure was cut is facing down as the strip is placed on the horizontal platform of the Tester.

The average overhang length is determined by averaging the sixteen (16) readings obtained on a fibrous structure.

${{{Overhang}{Length}{MD}} = \frac{{Sum}{of}{}8{MD}{readings}}{8}}{{{Overhang}{Length}{CD}} = \frac{{Sum}{of}{}8{CD}{readings}}{8}}{{{Overhang}{Length}{Total}} = \frac{{Sum}{of}{}{all}16{readings}}{16}}{{{Bend}{Length}{MD}} = \frac{{Overhang}{Length}{MD}}{2}}{{{Bend}{Length}{CD}} = \frac{{Overhang}{Length}{CD}}{2}}{{{Bend}{Length}{Total}} = \frac{{Overhang}{Length}{Total}}{2}}{{{Flexural}{Rigidity}} = {0.1629 \times W \times C^{3}}}$

wherein W is the basis weight of the fibrous structure in lbs/3000 ft²; C is the bending length (MD or CD or Total) in cm; and the constant 0.1629 is used to convert the basis weight from English to metric units. The results are expressed in mg-cm.

GM Flexural Rigidity=Square root of (MD Flexural Rigidity×CD Flexural Rigidity)

Slip Stick Coefficient of Friction Test Method:

Background

Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Of particular interest here, ‘dry’ friction resists relative lateral motion of two solid surfaces in contact. Dry friction is subdivided into static friction between non-moving surfaces, and kinetic friction between moving surfaces. “Slip Stick”, as applied here, is the term used to describe the dynamic variation in kinetic friction.

Friction is not itself a fundamental force but arises from fundamental electromagnetic forces between the charged particles constituting the two contacting surfaces. Textured surfaces also involve mechanical interactions, as is the case when sandpaper drags against a fibrous substrate. The complexity of these interactions makes the calculation of friction from first principles impossible and necessitates the use of empirical methods for analysis and the development of theory. As such, a specific sled material and test method was identified, and has shown correlation to human perception of surface feel.

This Slip Stick Coefficient of Friction Test Method measures the interaction of a diamond file (120-140 grit) against a surface of a test sample, in this case a fibrous structure and/or sanitary tissue product, at a pressure of about 32 g/in² as shown in FIGS. 15-17. The friction measurements are highly dependent on the exactness of the sled material surface properties, and since each sled has no ‘standard’ reference, sled-to-sled surface property variation is accounted for by testing a test sample with multiple sleds, according to the equipment and procedure described below.

Equipment and Set-Up

A Thwing-Albert (14 W. Collings Ave., West Berlin, N.J.) friction/peel test instrument (model 225-1) or equivalent if no longer available, is used, equipped with data acquisition software and a calibrated 2000 gram load cell that moves horizontally across the platform. Attached to the load cell is a small metal fitting (defined here as the “load cell arm”) which has a small hole near its end, such that a sled string can be attached (for this method, however, no string will be used). Into this load cell arm hole, insert a cap screw (¾ inch #8-32) by partially screwing it into the opening, so that it is rigid (not loose) and pointing vertically, perpendicular to the load cell arm.

After turning instrument on, set instrument test speed to 2 inches/min, test time to 10 seconds, and wait at least 5 minutes for instrument to warm up before re-zeroing the load cell (with nothing touching it) and testing. Force data from the load cell is acquired at a rate of 52 points per second, reported to the nearest 0.1 gram force. Press the ‘Return’ button to move crosshead 201 to its home position.

A smooth surfaced metal test platform 200, with dimensions of 5 inches by 4 inches by ¾ inch thick, is placed on top of the test instrument platen surface, on the left hand side of the load cell 203, with one of its 4 inch by ¾ inch sides facing towards the load cell 203, positioned 1.125 inches d from the left most tip of the load cell arm 202 as shown in FIGS. 15 and 17.

Sixteen test sleds 204 are required to perform this test (32 different sled surface faces). Each is made using a dual sided, wide faced diamond file 206 (25 mm×25 mm, 120/140 grit, 1.2 mm thick, McMaster-Carr part number 8142A14) with 2 flat metal washers 208 (approximately 11/16th inch outer diameter and about 11/32nd inch inner diameter). The combined weight of the diamond file 206 and 2 washers 208 is 11.7 grams +/−0.2 grams (choose different washers until weight is within this range). Using a metal bonding adhesive (Loctite 430, or similar), adhere the 2 washers 208 to the c-shaped end 210 of the diamond file 206 (one each on either face), aligned and positioned such that the opening 212 is large enough for the cap screw 214 to easily fit into, and to make the total length of sled 204 to approximately 3 inches long. Clean sled 204 by dipping it, diamond face end 216 only, into an acetone bath, while at the same time gently brushing with soft bristled toothbrush 3-6 times on both sides of the diamond file 206. Remove from acetone and pat dry each side with Kimwipe tissue (do not rub tissue on diamond surface, since this could break tissue pieces onto sled surface). Wait at least 15 minutes before using sled 204 in a test. Label each side of the sled 204 (on the arm or washer, not on the diamond face) with a unique identifier (i.e., the first sled is labeled “1 a” on one side, and “1 b” on its other side). When all 16 sleds 204 are created and labeled, there are then 32 different diamond face surfaces for available for testing, labeled 1 a and 1 b through 16 a and 16 b. These sleds 204 must be treated as fragile (particularly the diamond surfaces) and handled carefully; thus, they are stored in a slide box holder, or similar protective container.

Sample Prep

If sample to be tested is bath tissue, in perforated roll form, then gently remove 8 sets of 2 connected sheets from the roll, touching only the corners (not the regions where the test sled will contact). Use scissors or other sample cutter if needed. If sample is in another form, cut 8 sets of sample approximately 8 inches long in the MD, by approximately 4 inches long in the CD, one usable unit thick each. Make note and/or a mark that differentiates both face sides of each sample (e.g., fabric side or wire side, top or bottom, etc.). When sample prep is complete, there are 8 sheets prepared with appropriate marking that differentiates one side from the other. These will be referred to hereinafter as: sheets #1 through #8, each with a top side and a bottom side.

Test Operation

Press the ‘Return’ button to ensure crosshead 201 is in its home position.

Without touching test area of sample, place sheet #1 218 on test platform 200, top side facing up, aligning one of the sheet's CD edges (i.e. edge that is parallel to the CD) along the platform 218 edge closest to the load cell 202 (+/−1 mm). This first test (pull), of 32 total, will be in the MD direction on the top side of the sheet 218. Place a brass bar weight or equivalent 220 (1 inch diameter, 3.75 inches long) on the sheet 218, near its center, aligned perpendicular to the sled pull direction, to prevent sheet 218 from moving during the test. Place test sled “1 a” 204 over cap screw head 214 (i.e., sled washer opening 212 over cap screw head 214, and sled side 1 a is facing down) such that the diamond file 206 surface is lying flat and parallel on the sheet 218 surface and the cap screw 214 is touching the inside edge of the washers 208.

Gently place a cylindrically shaped brass 20 gram (+/−0.01 grams) weight 222 on top of the sled 204, with its edge aligned and centered with the sled's back end. Initiate the sled movement m and data acquisition by pressing the ‘Test’ button on the instrument. The test set up is shown in FIG. 17. The computer collects the force (grams) data and, after approximately 10 seconds of test time, this first of 32 test pulls of the overall test is complete.

If the test pull was set-up correctly, the diamond file 206 face (25 mm by 25 mm square) stays in contact with the sheet 218 during the entire 10 second test time (i.e., does not overhang over the sheet 218 or test platform 200 edge). Also, if at any time during the test the sheet 218 moves, the test is invalid, and must be rerun on another untouched portion of the sheet 218, using a heavier brass bar weight or equivalent 220 to hold sheet 218 down. If the sheet 218 rips or tears, rerun the test on another untouched portion of the sheet 218 (or create a new sheet 218 from the sample). If it rips again, then replace the sled 204 with a different one (giving it the same sled name as the one it replaced). These statements apply to all 32 test pulls.

For the second of 32 test pulls (also an MD pull, but in the opposite direction on the sheet), first remove the 20 gram weight 222, the sled 204, and the brass bar weight or equivalent 220 from the sheet 218. Press the ‘Return’ button on the instrument to reset the crosshead 201 to its home position. Rotate the sheet 218 180° (with top side still facing up), and replace the brass bar weight or equivalent 220 onto the sheet 218 (in the same position described previously). Place test sled “1 b” 204 over the cap screw head 214 (i.e., sled washer opening 212 over cap screw head 214, and sled side 1 b is facing down) and the 20 gram weight 222 on the sled 204, in the same manner as described previously. Press the ‘Test’ button to collect the data for the second test pull.

The third test pull will be in the CD direction. After removing the sled 204, weights 220, 222, and returning the crosshead 201, the sheet 218 is rotated 90° from its previous position (with top side still facing up), and positioned so that its MD edge is aligned with the test platform 200 edge (+/−1 mm). Position the sheet 218 such that the sled 204 will not touch any perforation, if present, or touch the area where the brass bar weight or equivalent 220 rested in previous test pulls. Place the brass bar weight or equivalent 220 onto the sheet 218 near its center, aligned perpendicular to the sled pull direction m. Place test sled “2 a” 204 over the cap screw head 214 (i.e., sled washer opening 212 over cap screw head 214, and sled side 2 a is facing down) and the 20 gram weight 222 on the sled 204, in the same manner as described previously. Press the ‘Test’ button to collect the data for the third test pull.

The fourth test pull will also be in the CD, but in the opposite direction and on the opposite half section of the sheet 218. After removing the sled 204, weights 220, 222, and returning the crosshead 201, the sheet 218 is rotated 180° from its previous position (with top side still facing up), and positioned so that its MD edge is again aligned with the test platform 200 edge (+/−1 mm). Position the sheet 218 such that the sled 204 will not touch any perforation, if present, or touch the area where the brass bar weight or equivalent 220 rested in previous test pulls. Place the brass bar weight or equivalent 220 onto the sheet 218 near its center, aligned perpendicular to the sled pull direction m. Place test sled “2 b” 204 over the cap screw head 214 (i.e., sled washer opening 212 over cap screw head 214, and sled side 2 b is facing down) and the 20 gram weight 222 on the sled 204, in the same manner as described previously. Press the ‘Test’ button to collect the data for the fourth test pull.

After the fourth test pull is complete, remove the sled 204, weights 220, 222, and return the crosshead 201 to the home position. Sheet #1 218 is discarded.

Test pulls 5-8 are performed in the same manner as 1-4, except that sheet #2 218 has its bottom side now facing upward, and sleds 3 a, 3 b, 4 a, and 4 b are used.

Test pulls 9-12 are performed in the same manner as 1-4, except that sheet #3 218 has its top side facing upward, and sleds 5 a, 5 b, 6 a, and 6 b are used.

Test pulls 13-16 are performed in the same manner as 1-4, except that sheet #4 218 has its bottom side facing upward, and sleds 7 a, 7 b, 8 a, and 8 b are used.

Test pulls 17-20 are performed in the same manner as 1-4, except that sheet #5 218 has its top side facing upward, and sleds 9 a, 9 b, 10 a, and 10 b are used.

Test pulls 21-24 are performed in the same manner as 1-4, except that sheet #6 218 has its bottom side facing upward, and sleds 11 a, 11 b, 12 a, and 12 b are used.

Test pulls 25-28 are performed in the same manner as 1-4, except that sheet #7 218 has its top side facing upward, and sleds 13 a, 13 b, 14 a, and 14 b are used.

Test pulls 29-32 are performed in the same manner as 1-4, except that sheet #8 218 has its bottom side facing upward, and sleds 15 a, 15 b, 16 a, and 16 b are used.

Calculations and Results

The collected force data (grams) is used to calculate Slip Stick COF for each of the 32 test pulls, and subsequently the overall average Slip Stick COF for the sample being tested. In order to calculate Slip Stick COF for each test pull, the following calculations are made. First, the standard deviation is calculated for the force data centered on 131st data point (which is 2.5 seconds after the start of the test) +/−26 data points (i.e., the 53 data points that cover the range from 2.0 to 3.0 seconds). This standard deviation calculation is repeated for each subsequent data point, and stopped after the 493rd point (about 9.5 sec). The numerical average of these 363 standard deviation values is then divided by the sled weight (31.7 g) and multiplied by 10,000 to generate the Slip Stick COF*10,000 for each test pull. This calculation is repeated for all 32 test pulls. The numerical average of these 32 Slip Stick COF*10,000 values is the reported value of the Slip Stick COF*10,000 for the sample. For simplicity, it is referred to as just Slip Stick COF, or more simply as Slip Stick, without units (dimensionless), and is reported to the nearest 1.0.

Outliers and Noise

It is not uncommon, with this described method, to observe about one out of the 32 test pulls to exhibit force data with a harmonic wave of vibrations superimposed upon it. For whatever reason, the pulled sled periodically gets into a relatively high frequency, oscillating ‘shaking’ mode, which can be seen in graphed force vs. time. The sine wave-like noise was found to have a frequency of about 10 sec-1 and amplitude in the 3-5 grams force range. This adds a bias to the true Slip Stick result for that test; thus, it is appropriate for this test pull be treated as an outlier, the data removed, and replaced with a new test of that same scenario (e.g., CD top face) and sled number (e.g. 3 a).

To get an estimate of the overall measurement noise, ‘blanks’ were run on the test instrument without any touching the load cell (i.e., no sled). The average force from these tests is zero grams, but the calculated Slip Stick COF was 66. Thus, it is speculated that, for this instrument measurement system, this value represents that absolute lower limit for Slip Stick COF.

In the interests of brevity and conciseness, any ranges of values set forth in this specification are to be construed as written description support for Claims reciting any sub-ranges having endpoints which are whole number values within the specified range in question. By way of a hypothetical illustrative example, a disclosure in this specification of a range of 1-5 shall be considered to support Claims to any of the following sub-ranges: 1-4; 1-3; 1-2; 2-5; 2-4; 2-3; 3-5; 3-4; and 4-5.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.”

Every document cited herein, including any cross referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. 

What is claimed is:
 1. A compacted fibrous structure article comprising a fibrous structure article such that the compacted fibrous structure article exhibits an Average Overall Density of less than 0.65 g/cm³ as measured according to the μCT Compacted/Compressed Fibrous Structure Article Test Method.
 2. The compacted fibrous structure article according to claim 1 wherein the compacted fibrous structure article exhibits a first portion exhibiting a first density value and a second portion exhibiting a second density value such that a minimum difference between the first density value and the second density value is at least 1% as measured according to the μCT Compacted/Compressed Fibrous Structure Article Test Method.
 3. The compacted fibrous structure article according to claim 1 wherein the fibrous structure article comprises a nonwoven fibrous structure.
 4. The compacted fibrous structure article according to claim 1 wherein the fibrous structure article comprises a plurality of fibrous elements.
 5. The compacted fibrous structure article according to claim 4 wherein the plurality of fibrous elements comprise a plurality of fibers.
 6. The compacted fibrous structure article according to claim 5 wherein the plurality of fibers comprise a plurality of pulp fibers.
 7. The compacted fibrous structure article according to claim 6 wherein the plurality of pulp fibers comprise a plurality of wood pulp fibers.
 8. The compacted fibrous structure article according to claim 1 wherein the fibrous structure article comprises a wet-laid fibrous structure.
 9. The compacted fibrous structure article according to claim 8 wherein the wet-laid fibrous structure comprises a structured fibrous structure.
 10. The compacted fibrous structure article according to claim 9 wherein the structured fibrous structure comprises a through-air-dried fibrous structure.
 11. The compacted fibrous structure article according to claim 10 wherein the through-air-dried fibrous structure comprises a creped through-air-dried fibrous structure.
 12. The compacted fibrous structure article according to claim 10 wherein the through-air-dried fibrous structure comprises an uncreped through-air-dried fibrous structure.
 13. The compacted fibrous structure article according to claim 8 wherein the structured fibrous structure comprises an ATMOS fibrous structure.
 14. The compacted fibrous structure article according to claim 8 wherein the structured fibrous structure comprises an NTT fibrous structure.
 15. The compacted fibrous structure article according to claim 8 wherein the structured fibrous structure comprises a belt creped fibrous structure.
 16. The compacted fibrous structure article according to claim 8 wherein the structured fibrous structure comprises a fabric creped fibrous structure.
 17. The compacted fibrous structure article according to claim 1 wherein the fibrous structure article comprises a conventional wet-pressed fibrous structure.
 18. The compacted fibrous structure article according to claim 1 wherein the compacted fibrous structure article comprises an ingredient selected from the group consisting of: antibacterial agents, antimicrobial agents, odor controlling agents, odor masking agents, perfumes, dry soap particles, surfactants, for example lathering and/or foaming surfactants, surface softening agents, lotions, polishing agents, dusting agents, and mixtures thereof.
 19. The compacted fibrous structure article according to claim 1 wherein the compacted fibrous structure article comprises a tab.
 20. The compacted fibrous structure article according to claim 1 wherein the tab is a machine-generated tab. 